A371092 a(n) = floor((A000265(1+(3*n))+5)/6), where A000265 gives the odd part of its argument.

1, 1, 2, 1, 3, 1, 4, 2, 5, 2, 6, 3, 7, 1, 8, 4, 9, 3, 10, 5, 11, 1, 12, 6, 13, 4, 14, 7, 15, 2, 16, 8, 17, 5, 18, 9, 19, 2, 20, 10, 21, 6, 22, 11, 23, 3, 24, 12, 25, 7, 26, 13, 27, 1, 28, 14, 29, 8, 30, 15, 31, 4, 32, 16, 33, 9, 34, 17, 35, 3, 36, 18, 37, 10, 38, 19, 39, 5, 40, 20, 41, 11, 42, 21, 43, 1, 44, 22, 45, 12

Offset

0,3

Comments

When a(n) is applied to square array A257852 we obtain square array A002260, or in other words, a(n) applied to any odd number gives the index of the column where it is located in array A257852.

Links

Antti Karttunen, Table of n, a(n) for n = 0..16384

Formula

a(n) = a(4*n + 1) = a(16*n + 5) = a(64*n + 21) = ... = a(4^k * n + ((4^k)-1)/3).

Mathematica

A371092[n_] := With[{k = 3*n + 1}, Floor[(k/2^IntegerExponent[k, 2] + 5)/6]];
Array[A371092, 100, 0] (* Paolo Xausa, Apr 20 2024 *)

Prog

(PARI)
A000265(n) = (n>>valuation(n, 2));
A371092(n) = floor((A000265(1+(3*n))+5)/6);

Crossrefs

Cf. A000265, A002260, A257852, A371101.

Cf. also A371093.

Sequence in context: A115118 A115121 A323523 * A124072 A189357 A100053

Adjacent sequences: A371089 A371090 A371091 * A371093 A371094 A371095

Keyword

nonn

Author

Antti Karttunen, Apr 19 2024

Status

approved