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%I #14 Oct 03 2016 16:01:50
%S 8,43,70,105,146,194,248,307,374,448,528,615,707,805,910,1021,1138,
%T 1260,1388,1523,1664,1810,1963,2122,2287,2458,2635,2818,3007,3202,
%U 3403,3610,3823,4042,4267,4498,4735,4978
%N Position of numbers of form 3*n^2 in A025060 (numbers of form j*k + k*i + i*j, where 1 <=i < j < k).
%F It is conjectured that A000926 ends at 1848, in which case a(n) = 3*n^2+18*n-38 for all n >= 22. - _Robert Israel_, Sep 06 2016
%p N:= 10000: # to get positions of all 3*n^2 <= N
%p B:= sort(convert({seq(seq(seq(i*j + j*k + i*k, i=1..min(j-1, (N-j*k)/(j+k))),j=2..min(k-1,(N-k)/(1+k))),k=3..(N-2)/3)},list)):
%p count:= 1:
%p for n from 1 to floor(sqrt(N/3)) do
%p if member(3*n^2,B,A[count]) then count:= count+1 fi
%p od:
%p seq(A[i],i=1..count-1); # _Robert Israel_, Sep 06 2016
%K nonn
%O 1,1
%A _Clark Kimberling_
%E More terms and a(4)-a(7) corrected by _Gionata Neri_, Sep 06 2016