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A351451
a(n) = A064989(A092261(A003961(n))).
3
1, 1, 2, 1, 1, 2, 2, 1, 1, 1, 5, 2, 4, 2, 2, 1, 3, 1, 2, 1, 4, 5, 6, 2, 1, 4, 1, 2, 1, 2, 17, 1, 10, 3, 2, 1, 10, 2, 8, 1, 7, 4, 2, 5, 1, 6, 8, 2, 1, 1, 6, 4, 6, 1, 5, 2, 4, 1, 29, 2, 13, 17, 2, 1, 4, 10, 4, 3, 12, 2, 31, 1, 3, 10, 2, 2, 10, 8, 10, 1, 1, 7, 12, 4, 3, 2, 2, 5, 25, 1, 8, 6, 34, 8, 2
OFFSET
1,3
FORMULA
Multiplicative with a(p) = A064989(q+1) and a(p^e) = 1 for e > 1, where q = nextPrime(p) = A151800(p).
a(n) = A326042(n) / A351449(n).
PROG
(PARI)
A003961(n) = { my(f = factor(n)); for(i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); };
A048250(n) = factorback(apply(p -> p+1, factor(n)[, 1]));
A055231(n) = {my(f=factor(n)); for (k=1, #f~, if (f[k, 2] > 1, f[k, 2] = 0); ); factorback(f); } \\ From A055231
A064989(n) = { my(f = factor(n>>valuation(n, 2))); for(i=1, #f~, f[i, 1] = precprime(f[i, 1]-1)); factorback(f); };
KEYWORD
nonn,mult
AUTHOR
Antti Karttunen, Feb 11 2022
STATUS
approved