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A062824

a(n) = Ch(A005117(n)) where Ch(n) is Chowla's function and A005117(n) are the squarefree numbers.

0, 0, 0, 0, 5, 0, 7, 0, 0, 9, 8, 0, 0, 10, 13, 0, 15, 0, 41, 0, 14, 19, 12, 0, 21, 16, 0, 53, 0, 25, 0, 20, 0, 16, 22, 31, 0, 0, 33, 18, 77, 0, 26, 73, 0, 0, 39, 18, 89, 0, 43, 0, 22, 45, 32, 0, 20, 34, 49, 24, 0, 0, 113, 0, 86, 55, 0, 0, 105, 40, 0, 125, 28, 61, 24, 63, 44, 0, 46, 121, 0, 26, 69, 0, 149, 0, 50, 73, 24, 34, 75, 0

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,5

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = A048050(A005117(n)). - Amiram Eldar, Mar 10 2024

MATHEMATICA

chowla[n_] := DivisorSigma[1, n] - n - 1; chowla[1] = 0; chowla /@ Select[Range[150], SquareFreeQ] (* Amiram Eldar, Mar 10 2024 *)

PROG

(PARI) j=[0]; for(n = 2, 150, if(issquarefree(n), j = concat(j, sigma(n)-n-1))); j

CROSSREFS