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A286351
a(n) is the number of decompositions of 2^(n-1)*(2^n-1) into 3 nonnegative cubes.
0
0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 2, 0, 1, 0, 2, 0, 1, 6, 3, 0, 1, 1, 3, 0, 4, 1, 2, 1, 2, 2, 8, 0, 0, 0, 7, 3, 10, 1, 4, 1, 2, 3, 2
OFFSET
1,11
COMMENTS
From Giovanni Resta, May 09 2017: (Start)
The triples corresponding to n<=40 are reported in the cited paper. Those corresponding to a(41)-a(43) are:
41: (1806336, 90370048, 118874112), (9340200, 89678370, 119250526);
42: (24663948, 61547632, 211219316), (37015132, 42806240, 188598692),
(94126080, 154352128, 172803584);
43: (16384, 266321920, 270516224), (94478388, 245170170, 284820886).
(end)
LINKS
Maciej Ulas, A note on the Diophantine equation 2^(n-1)*(2^n-1)=x^3+y^3+z^3, arXiv:1705.01074 [math.NT], 2017. See Table 1 p. 4.
MATHEMATICA
Table[Length@ PowersRepresentations[2^(n - 1) (2^n - 1), 3, 3] - Boole[n == 1], {n, 17}] (* Michael De Vlieger, May 08 2017 *)
CROSSREFS
Sequence in context: A156663 A139366 A049767 * A091394 A029881 A347290
KEYWORD
nonn,more
AUTHOR
Michel Marcus, May 08 2017
EXTENSIONS
a(41)-a(43) from Giovanni Resta, May 09 2017
STATUS
approved