A350618 - OEIS

%I #33 Jul 27 2024 23:53:19

%S 3,6,8,8,12,16,18,28,30,44,42,58,70,78,86,96,62,92,90,116,102,130,148,

%T 126,160,106,156,146,182,204,178,220,192,142,220,206,260,228,224,180,

%U 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

%N Terms in A350877 that immediately follow an odd term.

%C a(n) = A350617(n) + prime(n). Also a(n) = 2^A350833(n) * A350617(n+1).

%C 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.

%C 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.

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

%H N. J. A. Sloane, <a href="/A350618/b350618.txt">Table of n, a(n) for n = 1..20000</a> (first 10000 terms from Michael De Vlieger)

%t 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 *)

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

%K nonn

%O 1,1

%A _N. J. A. Sloane_, Jan 23 2022, revised Jan 28 2022