The prime number sequence starts with: `2,3,5,7,11,13,17,19...`. Notice that `2` is in position `one`. 

`3` occupies position `two`, which is a prime-numbered position. Similarly, `5`, `11` and `17` also occupy prime-numbered positions. We shall call primes such as `3,5,11,17` dominant primes because they occupy prime-numbered positions in the prime number sequence. Let's call this `listA`. 

As you can see from listA, for the prime range `range(0,10)`, there are `only two` dominant primes (`3` and `5`) and the sum of these primes is: `3 + 5 = 8`. 

Similarly, as shown in listA, in the `range (6,20)`, the dominant primes in this range are `11` and `17`, with a sum of `28`.

Given a `range (a,b)`, what is the sum of dominant primes within that range? Note that  `a <= range <= b` and `b` will not exceed `500000`.

Good luck!

If you like this Kata, you will enjoy:

[Simple Prime Streaming](https://www.codewars.com/kata/5a908da30025e995880000e3)

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[Divisor harmony](https://www.codewars.com/kata/59bf97cd4f98a8b1cd00007e)

```python

USER_FILENAME = "<user_code>"
import sys, json, builtins
import math, heapq, bisect, itertools, functools, collections, statistics, fractions, decimal, operator, array, random, re, string, os, pathlib
try:
    import resource as _res
except Exception:
    _res = None
from collections import Counter, defaultdict, deque, OrderedDict
from functools import lru_cache, reduce
from itertools import accumulate, permutations, combinations, product
from math import gcd, ceil, floor, sqrt
from decimal import Decimal
try:
    from typing import *
except Exception:
    pass
try:
    sys.setrecursionlimit(1_000_000)
except Exception:
    pass
try:
    import site as _site
    try:
        _sys_sites = _site.getsitepackages() if hasattr(_site, "getsitepackages") else []
        for _p in _sys_sites:
            if _p and _p not in sys.path:
                sys.path.append(_p)
    except Exception:
        pass
    try:
        _usp = _site.getusersitepackages()
        if isinstance(_usp, str):
            _usp = [_usp]
        for _p in _usp:
            if _p and _p not in sys.path:
                sys.path.append(_p)
    except Exception:
        pass
except Exception:
    pass

def _disabled_input(*args, **kwargs):
    raise RuntimeError("input() is disabled in callable mode")
builtins.input = _disabled_input

ns = {"__name__": "__judge__"}  # prevent if __name__ == "__main__" blocks
for _k, _v in list(globals().items()):
    if not _k.startswith("_"):
        ns[_k] = _v
_CODE = 'def solve(a, b):\n    primes = [False,2] + [x for x in range(3, b+1, 2) if all(x % d for d in range(3, int(x**.5+1), 2))]\n    dom_pos = [primes[x] for x in primes if x < len(primes)]\n    return sum(x for x in dom_pos if a <= x <= b)'
_co = compile(_CODE, USER_FILENAME, "exec")
exec(_co, ns, ns)

_target = None
_fn_name = 'solve'
if _fn_name:
    if "Solution" in ns:
        try:
            _obj = ns["Solution"]()
            if hasattr(_obj, _fn_name):
                _target = getattr(_obj, _fn_name)
        except Exception:
            _target = None
    if _target is None and _fn_name in ns and callable(ns[_fn_name]):
        _target = ns[_fn_name]
# Fallback: if there's exactly one user-defined function, use it
if _target is None:
    _cands = [v for k, v in ns.items() if callable(v) and getattr(v, "__module__", "") in ("__judge__", "__main__")]
    _user_funcs = [c for c in _cands if getattr(c, "__name__", "").startswith("_") is False]
    if len(_user_funcs) == 1:
        _target = _user_funcs[0]
if _target is None:
    raise RuntimeError(f"Could not resolve callable '{_fn_name}'")

_raw = sys.stdin.read().strip()
if _raw:
    _parsed = json.loads(_raw)
    if isinstance(_parsed, dict):
        _kwargs = _parsed.get("kwargs", {})
        _args = _parsed.get("args", [])
    else:
        _args, _kwargs = _parsed, {}
else:
    _args, _kwargs = [], {}
if not isinstance(_args, (list, tuple)):
    _args = [_args]
_res = _target(*_args, **_kwargs)
try:
    sys.stdout.write(repr(_res) + "\n")
except Exception:
    pass

```

Measured memory_bytes: 6614