A337657 Let M_k denote the addition table for the first k terms of A337656. M_k contains exactly k*(k+1)/2 distinct numbers, and these numbers are a subset of the entries in M_{k+1}. The present sequence consists of the numbers that never appear in any M_k.

5, 9, 11, 16, 17, 18, 22, 25, 26, 28, 29, 34, 35, 36, 38, 39, 41, 43, 46, 48, 49, 52, 53, 54, 55, 57, 58, 59, 61, 62, 63, 67, 69, 70, 71, 73, 75, 76, 78, 79, 80, 81, 82, 83, 84, 86, 87, 89, 90, 93, 96, 97, 99, 100, 101, 102, 104, 105, 106, 112, 113, 115, 116, 117, 118, 120, 124, 126, 128

Offset

1,1

Comments

Note that if A337656(k+1) = t, all entries in M_{k+1} that are not entries in M_k are >= t.

Links

Rémy Sigrist, Table of n, a(n) for n = 1..10000

Rémy Sigrist, C++ program for A337657

Example

The addition table, M_9:
   + |  0  1  3  7 12 20 30  44  65
-----+-----------------------------
   0 |  0
   1 |  1  2
   3 |  3  4  6
   7 |  7  8 10 14
  12 | 12 13 15 19 24
  20 | 20 21 23 27 32 40
  30 | 30 31 33 37 42 50 60
  44 | 44 45 47 51 56 64 74  88
  65 | 65 66 68 72 77 85 95 109 130

Prog

(C++) See Links section.

Crossrefs

Cf. A337655, A337656, A337658.

Sequence in context: A137011 A171629 A102178 * A314594 A314595 A314596

Adjacent sequences: A337654 A337655 A337656 * A337658 A337659 A337660

Keyword

nonn

Author

N. J. A. Sloane, Oct 01 2020

Status

approved