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A353524
A003557 applied to the prime shadow of primorial base exp-function: a(n) = A003557(A181819(A276086(n))).
3
1, 1, 1, 2, 1, 1, 1, 2, 2, 4, 1, 2, 1, 1, 1, 2, 3, 3, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1, 2, 2, 4, 1, 2, 2, 4, 4, 8, 2, 4, 1, 2, 2, 4, 3, 6, 1, 2, 2, 4, 1, 2, 1, 2, 2, 4, 1, 2, 1, 1, 1, 2, 3, 3, 1, 2, 2, 4, 3, 6, 3, 3, 3, 6, 9, 9, 1, 1, 1, 2, 3, 3, 1, 1, 1, 2, 3, 3, 1, 1, 1, 2, 1, 1, 1, 2, 2, 4, 1, 2, 1, 1, 1, 2
OFFSET
0,4
FORMULA
For n > 0, a(n) = A353576(n) / A353577(n).
PROG
(PARI)
A003557(n) = (n/factorback(factorint(n)[, 1]));
A181819(n) = factorback(apply(e->prime(e), (factor(n)[, 2])));
A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
KEYWORD
nonn,base
AUTHOR
Antti Karttunen, Apr 30 2022
STATUS
approved