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A350618
Terms in A350877 that immediately follow an odd term.
7
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^A350833(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 *)
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Jan 23 2022, revised Jan 28 2022
STATUS
approved