A353356 Numbers k for which A353328(k) > A353329(k). Positions of 1's in A353354.

2, 5, 10, 11, 16, 17, 22, 23, 30, 31, 34, 40, 41, 46, 47, 54, 55, 59, 62, 66, 67, 70, 73, 80, 82, 83, 85, 88, 94, 97, 102, 103, 109, 115, 118, 127, 128, 130, 134, 135, 136, 137, 138, 146, 149, 154, 155, 157, 165, 166, 167, 176, 179, 184, 186, 187, 190, 191, 194, 197, 205, 206, 211, 218, 227, 233, 235, 238, 240, 241

Offset

1,1

Comments

For any term k present here, A003961(k) is present in A353357.

Links

Table of n, a(n) for n=1..70.

Index entries for sequences computed from indices in prime factorization

Formula

a(n : n >= 1} = {m : tau(m) * A048675(m) == 2 (mod 3)}, where tau is the number of divisors function, A000005.

Prog

(PARI)
A332823(n) = { my(f = factor(n), u=(sum(k=1, #f~, f[k, 2]*2^primepi(f[k, 1]))/2)%3); if(2==u, -1, u); };
A353354(n) = sumdiv(n, d, A332823(d));
isA353356(n) = (0<A353354(n));
(PARI)
A048675(n) = { my(f = factor(n)); sum(k=1, #f~, f[k, 2]*2^primepi(f[k, 1]))/2; };
isA353356(n) = (2==((numdiv(n)*A048675(n))%3));

Crossrefs

Cf. A000005, A003961, A048675, A332823, A353328, A353329, A353354, A353355, A353357.

Sequence in context: A056704 A230408 A163624 * A363890 A257031 A378915

Adjacent sequences: A353353 A353354 A353355 * A353357 A353358 A353359

Keyword

nonn

Author

Antti Karttunen and Peter Munn, Apr 15 2022

Status

approved