An element replication device (11-k, 11'-k, 21-k, 21'-k) for replicating, by secure computation, replication source elements of a vector of replication source elements a(f),..., a(f), wherein the replication source elements are from a first vector a,..., a of elements and wherein 2 ≤ M ≤ N, comprising: a first arithmetic unit (114-k, 214-k, 214'-k) configured to obtain a concealed text of a second vector of elements a5,..., a5 by secure computation; and a second arithmetic unit (115-k) configured to obtain, by secure computation, a concealed text of a third vector of elements b,..., b by using the concealed text of the second vector, wherein a concealed text of α represents information obtained by concealing α with a concealing method enabling secure computation, and the concealing method is secret sharing or homomorphic encryption, characterized in that: the replication source elements appear in the same order in the vector of replication source elements a(f),..., a(f) as in the first vector; an additive inverse of a replication source element a(f(h-1)) is -a(f(h-1)), where h=2,..., M holds, the second vector is obtained by setting each replication source element a(f(h)) included in the first vector to an element a(f(h))-a(f(h-1)) and setting elements other than the replication source elements a(f),..., a(f) in the first vector to zero with respect to h=2,..., M, and the third vector includes a first element b =a5 and ith element b(i)=b(i-1)+a5(i) for i=2,..., N, wherein the first arithmetic unit is configured to obtain the concealed text of the second vector from a concealed text of a fourth vector formed only of the replication source elements a(f),..., a(f), or the first arithmetic unit is configured to use the concealed text of the first vector, a concealed text of information indicating whether or not the elements of the first vector are the replication source elements a(f),..., a(f), and a concealed text of information serving as a mark of the order of each element of the first vector to obtain the concealed text of the second vector. a first arithmetic unit (114-k, 214-k, 214'-k) configured to obtain a concealed text of a second vector of elements a5,..., a5 by secure computation; and a second arithmetic unit (115-k) configured to obtain, by secure computation, a concealed text of a third vector of elements b,..., b by using the concealed text of the second vector, wherein a concealed text of α represents information obtained by concealing α with a concealing method enabling secure computation, and the concealing method is secret sharing or homomorphic encryption, characterized in that: the replication source elements appear in the same order in the vector of replication source elements a(f),..., a(f) as in the first vector; an additive inverse of a replication source element a(f(h-1)) is -a(f(h-1)), where h=2,..., M holds, the second vector is obtained by setting each replication source element a(f(h)) included in the first vector to an element a(f(h))-a(f(h-1)) and setting elements other than the replication source elements a(f),..., a(f) in the first vector to zero with respect to h=2,..., M, and the third vector includes a first element b =a5 and ith element b(i)=b(i-1)+a5(i) for i=2,..., N, wherein the first arithmetic unit is configured to obtain the concealed text of the second vector from a concealed text of a fourth vector formed only of the replication source elements a(f),..., a(f), or the first arithmetic unit is configured to use the concealed text of the first vector, a concealed text of information indicating whether or not the elements of the first vector are the replication source elements a(f),..., a(f), and a concealed text of information serving as a mark of the order of each element of the first vector to obtain the concealed text of the second vector. the replication source elements appear in the same order in the vector of replication source elements a(f),..., a(f) as in the first vector; an additive inverse of a replication source element a(f(h-1)) is -a(f(h-1)), where h=2,..., M holds, the second vector is obtained by setting each replication source element a(f(h)) included in the first vector to an element a(f(h))-a(f(h-1)) and setting elements other than the replication source elements a(f),..., a(f) in the first vector to zero with respect to h=2,..., M, and the third vector includes a first element b =a5 and ith element b(i)=b(i-1)+a5(i) for i=2,..., N, wherein the first arithmetic unit is configured to obtain the concealed text of the second vector from a concealed text of a fourth vector formed only of the replication source elements a(f),..., a(f), or the first arithmetic unit is configured to use the concealed text of the first vector, a concealed text of information indicating whether or not the elements of the first vector are the replication source elements a(f),..., a(f), and a concealed text of information serving as a mark of the order of each element of the first vector to obtain the concealed text of the second vector.