OFFSET
1,2
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.
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 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Jeffrey Shallit, Jul 27 2017
STATUS
approved