login
A340147
a(n) = A247074(A003961(n)).
3
1, 1, 1, 3, 1, 2, 1, 9, 5, 3, 1, 3, 1, 5, 6, 27, 1, 10, 1, 9, 10, 6, 1, 18, 7, 8, 25, 15, 1, 3, 1, 81, 3, 9, 15, 15, 1, 11, 4, 27, 1, 5, 1, 9, 10, 14, 1, 27, 11, 21, 18, 6, 1, 50, 2, 45, 22, 15, 1, 18, 1, 18, 50, 243, 24, 12, 1, 27, 7, 3, 1, 90, 1, 20, 21, 33, 30, 16, 1, 81, 125, 21, 1, 30, 3, 23, 30, 54, 1, 15, 40, 21
OFFSET
1,4
COMMENTS
Prime shifted analog of A247074.
Each term a(n) is a divisor of A340072(n).
FORMULA
a(n) = A247074(A003961(n)).
a(n) = A003972(n) / A340148(n).
PROG
(PARI)
A003961(n) = { my(f = factor(n)); for(i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); };
A247074(n) = { my(f=factor(n)); eulerphi(f)/prod(i=1, #f~, gcd(f[i, 1]-1, n-1)); }; \\ From A247074
CROSSREFS
Sequence in context: A349380 A351425 A249580 * A011086 A321889 A321751
KEYWORD
nonn
AUTHOR
Antti Karttunen, Dec 30 2020
STATUS
approved