A326135 a(n) = sigma(A028234(n)), where sigma is the sum of divisors of n, and A028234 gives n without any occurrence of its smallest prime factor.

1, 1, 1, 1, 1, 4, 1, 1, 1, 6, 1, 4, 1, 8, 6, 1, 1, 13, 1, 6, 8, 12, 1, 4, 1, 14, 1, 8, 1, 24, 1, 1, 12, 18, 8, 13, 1, 20, 14, 6, 1, 32, 1, 12, 6, 24, 1, 4, 1, 31, 18, 14, 1, 40, 12, 8, 20, 30, 1, 24, 1, 32, 8, 1, 14, 48, 1, 18, 24, 48, 1, 13, 1, 38, 31, 20, 12, 56, 1, 6, 1, 42, 1, 32, 18, 44, 30, 12, 1, 78, 14, 24, 32, 48, 20, 4, 1

Offset

1,6

Links

Antti Karttunen, Table of n, a(n) for n = 1..16384

Antti Karttunen, Data supplement: n, a(n) computed for n = 1..65537

Index entries for sequences related to sigma(n)

Formula

a(n) = A000203(A028234(n)).

a(n) = A326065(n) / A000203(A020639(n)^(A067029(n)-1))).

Prog

(PARI)
A028234(n) = { my(f = factor(n)); if (#f~, f[1, 1] = 1); factorback(f); }; \\ From A028234
A326135(n) = sigma(A028234(n));

Crossrefs

Cf. A000203, A028234, A326065, A326136.

Sequence in context: A179054 A063928 A344910 * A318305 A306264 A321647

Adjacent sequences: A326132 A326133 A326134 * A326136 A326137 A326138

Keyword

nonn

Author

Antti Karttunen, Jun 08 2019

Status

approved