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 A320005 Number of proper divisors of n of the form 6*k + 5. 7
 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 1, 1, 1, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 1, 0, 0, 0, 1, 1, 0, 0, 0, 2, 0, 0, 1, 0, 1, 0, 0, 0, 0, 1, 1, 0, 1, 1, 2, 0, 0, 0, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 0, 2, 0, 1, 1, 0, 1, 0, 1, 0, 1, 1, 0, 0, 0, 1, 1, 0, 1, 0, 0, 2 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,55 LINKS Antti Karttunen, Table of n, a(n) for n = 1..65537 FORMULA a(n) = A319995(n) - [+5 = n (mod 6)], where [ ] is the Iverson bracket, giving 1 only when n = -1 mod 6, and 0 otherwise. a(n) = A320015(n) - A320001(n). a(n) = A007814(A319992(n)). G.f.: Sum_{k>=1} x^(12*k-2) / (1 - x^(6*k-1)). - Ilya Gutkovskiy, Apr 14 2021 PROG (PARI) A320005(n) = if(!n, n, sumdiv(n, d, (d

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Last modified September 26 13:25 EDT 2021. Contains 347668 sequences. (Running on oeis4.)