A339814 The exponent of the highest power of 2 dividing (A019565(2n) - 1).

1, 2, 1, 1, 2, 1, 3, 1, 5, 1, 2, 2, 1, 7, 1, 2, 1, 6, 1, 1, 4, 1, 2, 1, 2, 1, 5, 3, 1, 2, 1, 4, 1, 2, 1, 1, 2, 1, 3, 1, 4, 1, 2, 2, 1, 4, 1, 2, 1, 4, 1, 1, 5, 1, 2, 1, 2, 1, 4, 3, 1, 2, 1, 1, 3, 1, 2, 2, 1, 3, 1, 4, 1, 2, 1, 1, 2, 1, 3, 1, 2, 1, 3, 6, 1, 2, 1, 2, 1, 4, 1, 1, 5, 1, 2, 1, 3, 1, 2, 2, 1, 3, 1, 5, 1

Offset

1,2

Comments

The 2-adic valuation of A339809(2n).

Links

Antti Karttunen, Table of n, a(n) for n = 1..65537

Formula

a(n) = A007814(A339809(2*n)) = A007814(A019565(2*n)-1).

a(n) = A007814(A003961(A019565(n))-1).

Prog

(PARI)
A019565(n) = { my(m=1, p=1); while(n>0, p = nextprime(1+p); if(n%2, m *= p); n >>= 1); (m); };
A339814(n) = valuation((A019565(2*n)-1), 2);

Crossrefs

Bisection of A339813.

Cf. A003961, A007814, A019565, A339809, A339815, A339822.

Sequence in context: A034807 A275111 A182961 * A135062 A088428 A025838

Adjacent sequences: A339811 A339812 A339813 * A339815 A339816 A339817

Keyword

nonn

Author

Antti Karttunen, Dec 18 2020

Status

approved