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A332448
a(n) = A007814(A087808(sigma(n))).
3
0, 1, 2, 0, 2, 3, 3, 2, 0, 1, 3, 2, 1, 4, 4, 0, 1, 0, 2, 1, 5, 2, 4, 4, 0, 1, 3, 3, 3, 3, 5, 1, 5, 2, 5, 1, 2, 4, 3, 1, 1, 6, 4, 2, 1, 3, 5, 2, 0, 0, 3, 1, 2, 5, 3, 5, 4, 1, 4, 3, 1, 6, 3, 0, 2, 4, 2, 2, 6, 4, 3, 1, 1, 1, 2, 3, 6, 3, 4, 1, 0, 2, 2, 5, 3, 2, 5, 2, 1, 1, 4, 3, 7, 4, 5, 3, 1, 4, 2, 0, 2, 4, 3, 1, 7
OFFSET
1,3
FORMULA
PROG
(PARI)
A087808(n) = if(n<1, 0, if(n%2==0, 2*A087808(n/2), A087808((n-1)/2)+1));
A332448(n) = valuation(A087808(sigma(n)), 2);
CROSSREFS
Cf. A332443 (positions of zeros).
Sequence in context: A171731 A323212 A185815 * A184829 A321132 A003987
KEYWORD
nonn
AUTHOR
Antti Karttunen, Feb 14 2020
STATUS
approved