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A239114
Exponent of 2 in prime factorization (i.e., 2-adic valuation) of odd nonprimes A014076(n) + 1.
2
1, 1, 4, 1, 1, 2, 1, 2, 3, 1, 1, 2, 3, 1, 6, 1, 1, 2, 1, 1, 1, 3, 2, 1, 5, 2, 1, 4, 2, 1, 3, 1, 2, 1, 1, 1, 3, 1, 4, 1, 2, 1, 2, 5, 1, 1, 1, 2, 4, 1, 3, 1, 2, 1, 2, 1, 2, 1, 4, 1, 1, 3, 1, 2, 1, 1, 3, 2, 1, 2, 1, 3, 1, 1, 8, 2, 1, 1, 2, 1, 2, 3, 1, 5, 1, 2, 3, 1, 2, 1, 4, 1, 1, 2, 6, 1, 2, 1, 3, 1
OFFSET
1,3
COMMENTS
Sequence is counterpart to A023512, i.e., merging these two sequences gives the ruler function A001511.
FORMULA
a(n) = A001511((A014076(n)+1)/2)
EXAMPLE
a(13) = 3, because the 13th odd nonprime is 55, and the largest power of 2 dividing 55+1 is 3.
PROG
(PARI) lista(nn) = {forstep(n=1, nn, 2, if (! isprime(n), print1(valuation(n+1, 2), ", ")); ); } \\ Michel Marcus, Mar 13 2014
CROSSREFS
KEYWORD
nonn
AUTHOR
K. G. Stier, Mar 10 2014
STATUS
approved