A328523 a(n) = number of terms in A002182 that are of the form A002182(n)/p for some prime p|n.

0, 1, 1, 1, 2, 1, 1, 1, 1, 2, 2, 2, 2, 2, 1, 1, 2, 3, 3, 1, 1, 2, 1, 1, 1, 1, 2, 2, 2, 2, 3, 2, 2, 2, 2, 3, 2, 1, 1, 2, 3, 2, 2, 3, 2, 3, 3, 2, 2, 1, 3, 2, 1, 3, 1, 2, 2, 2, 2, 3, 2, 2, 4, 3, 1, 4, 2, 2, 2, 2, 1, 2, 2, 2, 2, 4, 3, 4, 3, 2, 3, 1, 1, 1, 1, 2, 2, 3

Offset

1,5

Comments

Conjecture: a(n) > 0 for n > 1. (This is false.)

It seems that a(815) = 0. - M. F. Hasler, Jan 08 2020

Links

Table of n, a(n) for n=1..88.

Prog

(PARI) apply( {a(n)=#[0|p<-factor(n=A2182[n])[, 1], setsearch(A2182, n/p)]}, [1..99]) \\ Uses global var. A2182 which must be assigned to a vector of at least n elements of that sequence. - M. F. Hasler, Jan 08 2020

Crossrefs

Cf. A002182, A199337, A330737.

Cf. A112778(n) = A001222(A002182(n)) (bigomega of HCN's).

Sequence in context: A112188 A112189 A112191 * A025887 A025882 A025876

Adjacent sequences: A328520 A328521 A328522 * A328524 A328525 A328526

Keyword

nonn

Author

David A. Corneth, Jan 04 2020

Status

approved