A258145 - OEIS

A258145

Row lengths of the irregular array in A256598.

1, 3, 2, 6, 7, 5, 3, 6, 4, 7, 2, 5, 8, 42, 6, 40, 9, 4, 7, 12, 41, 10, 5, 39, 8, 8, 3, 42, 11, 11, 6, 40, 9, 9, 4, 38, 43, 4, 7, 12, 7, 41, 2, 10, 10, 34, 5, 39, 44, 8, 8, 32, 13, 37, 42, 25, 3, 11, 6, 11, 35, 16, 40, 16, 45, 9, 9, 14, 33, 14, 4, 38, 43, 43, 7, 4, 12, 31, 12, 19, 36

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OFFSET

0,2

COMMENTS

a(n) is the number of odd numbers in row A070165(2*n+1) and also in row A070168(2*n+1), for n >= 0 (if it turns out that a row 2*n+1 has infinite row length one puts a(n) = 0).

LINKS

Table of n, a(n) for n=0..80.

FORMULA

a(n) = A078719(2*n+1) for n >= 0. - Torsten Messner, Feb 03 2026

PROG

(PARI) row(n) = {my(oddn = 2*n+1, vl = List(oddn), x); while (oddn != 1, x = 3*oddn+1; oddn = x >> valuation(x, 2); listput(vl, oddn)); Vec(vl); }

a(n) = #row(n); \\ Michel Marcus, Feb 03 2026

CROSSREFS

Cf. A256598, A070165, A070168, A078719.

Sequence in context: A335409 A236341 A293835 * A175930 A369272 A265346

Adjacent sequences: A258142 A258143 A258144 * A258146 A258147 A258148

KEYWORD

nonn,easy

AUTHOR

Wolfdieter Lang, May 27 2015

EXTENSIONS

More terms from Michel Marcus, Feb 03 2026

STATUS

approved