%I A115288
%S A115288 0,1,4,7,10,16,22,25,64,46,70,67,92,85,160,115,106,136,200,157,190,172,
%T A115288 256,235,568,277,370,337,400,367,340,550,556,442,1102,445,472,631,610,
%U A115288 535,682,697,652,1075,956,850,1984,865,1172,997,862,1081,1462,1135,1060
%N A115288 a(n) is the smallest number representable in exactly n ways as a sum
of 2 triangular numbers and one square (each of them >= 0).
%e A115288 a(4)=7 since 7 can be expressed in 4 ways, 7= T(3)+T(1)+0^2 = T(3)+T(0)+1^2
= T(2)+T(0)+2^2 = T(2)+T(2)+1^2 and none of the numbers from 0 to
6 can be expressed in 4 ways.
%t A115288 V=Table[0, {i, 2500}]; T[n]:=n(n+1)/2; Do[a=T[i]+T[j]+k^2;If[a<2500,
V[[a+1]]++ ], {i, 0, 71}, {j, 0, i}, {k, 0, 50}]; Table[Position[V,
z][[1, 1]]-1, {z, 60}]
%Y A115288 Cf. A115289, A000437, A061262.
%Y A115288 Sequence in context: A096676 A092863 A138694 this_sequence A153003 A128429
A131500
%Y A115288 Adjacent sequences: A115285 A115286 A115287 this_sequence A115289 A115290
A115291
%K A115288 nonn
%O A115288 1,3
%A A115288 Giovanni Resta (g.resta(AT)iit.cnr.it), Jan 19 2006
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