A290334 Numbers that are not the sum of three or fewer terms from A020330.

1, 2, 4, 5, 7, 8, 11, 12, 14, 17, 19, 22, 24, 26, 27, 29, 31, 32, 34, 37, 38, 41, 43, 44, 47, 50, 52, 53, 59, 62, 68, 71, 77, 80, 85, 86, 89, 92, 94, 95, 97, 98, 101, 103, 104, 106, 107, 110, 112, 113, 115, 116, 119, 121, 122, 124, 125, 128, 130, 131, 133, 134, 137, 138, 140, 143, 145, 147, 148, 150, 152, 155, 157, 158, 160, 164, 165

Offset: 1

Author

Jeffrey Shallit, Jul 27 2017

Keywords

• nonn

Comments

Not currently proved that there are infinitely many terms. It is conjectured that all integers > 686 are the sum of four binary squares.

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000
• Aayush Rajasekaran, Jeffrey Shallit and Tim Smith, Sums of Palindromes: an Approach via Nested-Word Automata, in: Rolf Niedermeier and Brigitte Vallée, 35th Symposium on Theoretical Aspects of Computer Science (STACS 2018), Schloss Dagstuhl, 2018, pp. 54:1-54:12; arXiv preprint, arXiv:1706.10206 [cs.FL], June 30 2017.

Crossrefs

Cf. A020330, A290335, A298731.

Programs

Mathematica

v = Table[n + n * 2^Floor[Log2[n] + 1], {n, 0, 12}]; Complement[Range[v[[-1]]], Plus @@@ Tuples[v, 3]] (* Amiram Eldar, Apr 09 2021 *)