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A341353 Greatest k such that 3^k divides A156552(n); the 3-adic valuation of A156552(n). 3
0, 0, 1, 0, 0, 0, 0, 1, 2, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 2, 1, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 3, 0, 0, 1, 1, 0, 0, 0, 0, 0, 3, 0, 0, 1, 0, 0, 0, 0, 0, 2, 0, 1, 0, 0, 0, 0, 1, 0, 2, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 1, 1, 0, 3, 3, 0, 2, 2, 0, 0, 2, 0, 0, 0, 0, 0, 1, 0, 2, 0, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,9

LINKS

Antti Karttunen, Table of n, a(n) for n = 2..65539

Index entries for sequences computed from indices in prime factorization

FORMULA

a(n) = A007949(A156552(n)).

a(p) = 0 for all primes p.

a(n^2) > 0 for all n >= 2.

a(n) > 0 iff A329903(n) = 0.

PROG

(PARI)

A007949(n) = valuation(n, 3);

A156552(n) = { my(f = factor(n), p2 = 1, res = 0); for(i = 1, #f~, p = 1 << (primepi(f[i, 1]) - 1); res += (p * p2 * (2^(f[i, 2]) - 1)); p2 <<= f[i, 2]); res };

A341353(n) = A007949(A156552(n));

CROSSREFS

Cf. A007949, A156552, A329609 (positions of nonzeros), A329903, A341354 (even bisection), A341355.

Cf. also A055396 (the 2-adic valuation + 1), A292251.

Sequence in context: A080224 A341508 A261488 * A010105 A341618 A337690

Adjacent sequences:  A341350 A341351 A341352 * A341354 A341355 A341356

KEYWORD

nonn

AUTHOR

Antti Karttunen, Feb 14 2021

STATUS

approved

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Last modified August 2 09:22 EDT 2021. Contains 346422 sequences. (Running on oeis4.)