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A331279
a(n) = A122111(A006047(n)).
1
1, 2, 4, 2, 3, 6, 4, 6, 9, 2, 3, 6, 3, 5, 10, 6, 10, 15, 4, 6, 9, 6, 10, 15, 9, 15, 25, 2, 3, 6, 3, 5, 10, 6, 10, 15, 3, 5, 10, 5, 7, 14, 10, 14, 21, 6, 10, 15, 10, 14, 21, 15, 21, 35, 4, 6, 9, 6, 10, 15, 9, 15, 25, 6, 10, 15, 10, 14, 21, 15, 21, 35, 9, 15, 25, 15, 21, 35, 25, 35, 49, 2, 3, 6, 3, 5, 10, 6, 10, 15, 3, 5, 10, 5, 7
OFFSET
0,2
LINKS
FORMULA
a(n) = A122111(A006047(n)).
For all n >= 0, A056239(a(n)) = A053735(n).
PROG
(PARI)
A006047(n) = { my(m=1, d); while(n, d = (n%3); m *= (1+d); n = (n-d)/3); m; };
A064989(n) = {my(f); f = factor(n); if((n>1 && f[1, 1]==2), f[1, 2] = 0); for (i=1, #f~, f[i, 1] = precprime(f[i, 1]-1)); factorback(f)};
A122111(n) = if(1==n, n, prime(bigomega(n))*A122111(A064989(n)));
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jan 13 2020
STATUS
approved