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A097366
Largest k such that 2^k divides A096421(n).
2
1, 2, 2, 3, 3, 5, 4, 8, 5, 7, 6, 7, 7, 10, 8, 9, 9, 11, 10, 11, 11, 13, 12, 15, 13, 16, 14, 17, 15, 17, 16, 18, 17, 21, 18, 19, 19, 21, 20, 23, 21, 23, 22, 23, 23, 27, 24, 27, 25, 27, 26, 27, 27, 29, 28, 30, 29, 33, 30, 31, 31, 33, 32, 34, 33, 35, 34, 36, 35, 38, 36, 39, 37, 39, 38
OFFSET
3,2
COMMENTS
Exponent of 2 in prime factorization of A096421(n).
Observation: a(n) = (n-1)/2 for odd n.
EXAMPLE
A096421(10) = 1792 = 2^8 * 7, so a(10) = 8.
PROG
(PARI) {m=77; v=vector(m); v[1]=1; for(n=2, m, s=0; for(j=1, n-1, if(gcd(j, n)==1, s=s+v[j]*v[n-j])); v[n]=s); for(i=3, m, print1(factor(v[i])[1, 2], ", "))}
CROSSREFS
Sequence in context: A036819 A351004 A114328 * A139807 A308465 A276119
KEYWORD
nonn
AUTHOR
Klaus Brockhaus, Aug 09 2004
STATUS
approved