A379495 a(n) = A019565(A001065(n)), where A019565 is the base-2 exp-function, and A001065 is the sum of proper divisors of n.

1, 2, 2, 6, 2, 15, 2, 30, 5, 7, 2, 11, 2, 21, 14, 210, 2, 110, 2, 165, 42, 105, 2, 65, 15, 11, 70, 385, 2, 273, 2, 2310, 210, 55, 70, 4290, 2, 165, 22, 429, 2, 2145, 2, 91, 26, 231, 2, 595, 7, 546, 110, 1365, 2, 51, 22, 17, 330, 13, 2, 7735, 2, 39, 182, 30030, 66, 1785, 2, 3003, 462, 357, 2, 102102, 2, 91, 286, 17, 66

Offset

1,2

Links

Antti Karttunen, Table of n, a(n) for n = 1..32768

Index entries for sequences related to binary expansion of n.

Index entries for sequences related to sigma(n).

Prog

(PARI)
A019565(n) = { my(m=1, p=1); while(n>0, p = nextprime(1+p); if(n%2, m *= p); n >>= 1); (m); };
A379495(n) = A019565(sigma(n)-n);

Crossrefs

Cf. A001065, A019565, A379496, A379501.

Cf. also A379493.

Sequence in context: A098555 A057562 A102628 * A211776 A325248 A036655

Adjacent sequences: A379492 A379493 A379494 * A379496 A379497 A379498

Keyword

nonn

Author

Antti Karttunen, Jan 05 2025

Status

approved