Deletion of Newberger's summation formula

Comment: Ideally I would have suggested to merge it with something, but since the article deriving the relation has only been cited 13 about 17 times since 1982 it doesn't seem to warrant throwing a relationship which is apparently used very rarely in with something important (e.g. Bessel function) just as a token gesture. I added references so  is OK, and as Ascidian  pointed out it would seem a name change is in order. And maybe someone can figure out why it's used in plasma applications so to expand the article
Stance: keep
Cited policy: Wikipedia:Verifiability (WP:V)