A350618 Terms in A350877 that immediately follow an odd term.

3, 6, 8, 8, 12, 16, 18, 28, 30, 44, 42, 58, 70, 78, 86, 96, 62, 92, 90, 116, 102, 130, 148, 126, 160, 106, 156, 146, 182, 204, 178, 220, 192, 142, 220, 206, 260, 228, 224, 180, 224, 188, 238, 312, 236, 258, 340, 308, 304, 248, 264, 272, 258, 380, 352, 274, 406, 474, 514, 538, 552, 362, 488, 372, 406, 520, 396, 436

Offset

1,1

Comments

a(n) = A350617(n) + prime(n). Also a(n) = 2^A350883(n) * A350617(n+1).

This is a compressed version of A350877: when A350877 reaches an even number e, the following steps repeatedly divide e by 2 until an odd number is reached. In the present sequence the results of those divisions are suppressed.

For example, A350877 (n>=2) begins 1, 3, 6, [3,] 8, [4, 2, 1,] 8, [4, 2, 1,] 12, [6, 3,] 16, [8, 4, 2, 1,] 18, ..., where the suppressed terms are enclosed in square brackets.

The scatterplot of the present sequence is the same as the red-colored portion of Sigrist's colored scatterplot in A350877.

Links

N. J. A. Sloane, Table of n, a(n) for n = 1..20000 (first 10000 terms from Michael De Vlieger)

Mathematica

j = 1; q = 2; Reap[Do[If[EvenQ[j], Set[k, j/2], Set[k, j + q]; Set[q, NextPrime[q]]]; If[OddQ[j], Sow[i + 1]]; j = k, {i, 2, 436}]][[-1, -1]] (* Michael De Vlieger, Jan 23 2022 *)

Crossrefs

Cf. A350877, A350615, A350616, A350617, A350619, A350620, A350621, A350833.

Sequence in context: A036265 A016663 A023993 * A133159 A188544 A163463

Adjacent sequences: A350615 A350616 A350617 * A350619 A350620 A350621

Keyword

nonn

Author

N. J. A. Sloane, Jan 23 2022, revised Jan 28 2022

Status

approved