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A339903
Fully multiplicative with a(p) = A000265(q-1), where q = A151800(p), the next prime > p.
4
1, 1, 1, 1, 3, 1, 5, 1, 1, 3, 3, 1, 1, 5, 3, 1, 9, 1, 11, 3, 5, 3, 7, 1, 9, 1, 1, 5, 15, 3, 9, 1, 3, 9, 15, 1, 5, 11, 1, 3, 21, 5, 23, 3, 3, 7, 13, 1, 25, 9, 9, 1, 29, 1, 9, 5, 11, 15, 15, 3, 33, 9, 5, 1, 3, 3, 35, 9, 7, 15, 9, 1, 39, 5, 9, 11, 15, 1, 41, 3, 1, 21, 11, 5, 27, 23, 15, 3, 3, 3, 5, 7, 9, 13, 33, 1, 25, 25
OFFSET
1,5
FORMULA
For all squarefree numbers k, a(k) = A339904(k).
PROG
(PARI)
A000265(n) = (n>>valuation(n, 2));
A339903(n) = if(1==n, n, my(f=factor(n)); for(i=1, #f~, f[i, 1] = nextprime(1+f[i, 1])-1); A000265(factorback(f)));
CROSSREFS
KEYWORD
nonn,mult
AUTHOR
Antti Karttunen, Dec 29 2020
STATUS
approved