A328319 Sum of digits when A328316(n) is written in primorial base; number of prime factors in A328316(1+n), counted with multiplicity.

0, 1, 1, 2, 1, 3, 3, 7, 21, 159, 12927, 132571335

Offset: 0

Author

Antti Karttunen, Oct 14 2019

Keywords

• nonn
• more
• hard

Links

• Index entries for sequences related to primorial base

Crossrefs

Cf. A001221, A276086, A276150, A328316, A328317, A328318, A328322.

Programs

PARI

A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
A328316(n) = if(!n,0,A276086(A328316(n-1)));
A276150(n) = { my(s=0, p=2, d); while(n, d = (n%p); s += d; n = (n-d)/p; p = nextprime(1+p)); (s); };
A328319(n) = A276150(A328316(n));
\\ Or alternatively, more slowly as:
A328319(n) = bigomega(A328316(1+n));

Formula

a(n) = A276150(A328316(n)).

a(n) = A001222(A328316(1+n)).