Search: id:A115289
Results 1-1 of 1 results found.

%I A115289
%S A115289 0,1,5,10,19,26,55,46,53,116,86,128,173,145,200,170,221,235,236,305,341,
%T A115289 326,491,425,548,431,676,530,536,635,656,851,905,695,1118,950,1040,1171,
%U A115289 1241,1031,1076,1115,1325,1661,1943,1391,1531,1691,1790,1670,2291,2081
%N A115289 a(n) is the smallest number representable in exactly n ways as a sum 
               of one triangular number and 2 squares (each of them >= 0).
%e A115289 a(4)=10 since 10 can be expressed in 4 ways,
%e A115289 10=T(4)+0^2+0^2 = T(3)+0^2+2^2 = T(1)+0^2+3^2 = T(0)+1^2+3^2 and none 
               of the numbers from 0 to 9 can be expressed in 4 ways.
%t A115289 V = Table[0, {i, 5000}]; T[n]:=n(n+1)/2; Do[a = T[i]+j^2+k^2; If[a<5000, 
               V[[a+1]]++ ], {i, 0, 100}, {j, 0, 71}, {k, 0, j}]; Table[Position[V, 
               z][[1, 1]]-1, {z, 60}]
%Y A115289 Cf. A115288, A000437, A061262.
%Y A115289 Sequence in context: A083287 A091922 A030776 this_sequence A134467 A047882 
               A053311
%Y A115289 Adjacent sequences: A115286 A115287 A115288 this_sequence A115290 A115291 
               A115292
%K A115289 nonn
%O A115289 1,3
%A A115289 Giovanni Resta (g.resta(AT)iit.cnr.it), Jan 19 2006

Search completed in 0.001 seconds