A348997 a(n) = A348733(A276086(n)), where A348733(n) = gcd(A003959(n), A034448(n)), and A276086 gives the prime product form of primorial base expansion of n.

1, 3, 4, 12, 2, 6, 6, 18, 24, 72, 12, 36, 2, 6, 8, 24, 4, 12, 18, 54, 72, 216, 36, 108, 2, 6, 8, 24, 4, 12, 8, 24, 32, 96, 16, 48, 48, 144, 192, 576, 96, 288, 16, 48, 64, 192, 32, 96, 144, 432, 576, 1728, 288, 864, 16, 48, 64, 192, 32, 96, 2, 6, 8, 24, 4, 12, 12, 36, 48, 144, 24, 72, 4, 12, 16, 48, 8, 24, 36, 108, 144

Offset

0,2

Links

Antti Karttunen, Table of n, a(n) for n = 0..11550

Index entries for sequences related to primorial base

Formula

a(n) = A348733(A276086(n)) = gcd(A348949(n), A348996(n)).

Prog

(PARI) A348997(n) = { my(m1=1, m2=1, p=2); while(n, if(n%p, m1 *= ((1+p)^(n%p)); m2 *= (1+(p^(n%p)))); n = n\p; p = nextprime(1+p)); gcd(m1, m2); };

Crossrefs

Cf. A003959, A034448, A276086, A348733, A348949, A348996.

Cf. also A346471 for similar construction. (Compare the scatter plots).

Sequence in context: A045826 A346471 A084200 * A354781 A097850 A238855

Adjacent sequences: A348994 A348995 A348996 * A348998 A348999 A349000

Keyword

nonn,base,look

Author

Antti Karttunen, Nov 07 2021

Status

approved