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%I #12 Dec 19 2024 23:40:34
%S 0,2,6,9,14,20,21,28,35,44,51,57,62,75,80,84,100,104,107,126,129,131,
%T 132,155,156,182,209,237,266,291,321,344,375,396,428,461,480,514,531,
%U 566,602,617,654,667,705,744,755,795,804,845,852,894,937,942,986,989,1034
%N Records of A064784.
%H Robert Israel, <a href="/A373327/b373327.txt">Table of n, a(n) for n = 1..10000</a>
%p R:= 0: m:= 0: count:= 1:
%p for i from 1 while count < 100 do
%p t:= i*(i+1)/2;
%p v:= t - floor(sqrt(t))^2;
%p if v > m then
%p R:= R,v; m:= v; count:= count+1;
%p fi
%p od:
%p R; # _Robert Israel_, Dec 19 2024
%o (PARI) a373327(nmax) = {my(m=-oo); for(n=0, nmax, my(T=n*(n+1)/2, d=T-sqrtint(T)^2); if(d>m, print1(d, ", "); m=d))};
%o a373327(750)
%Y A373328 gives the corresponding positions.
%Y Cf. A000217, A000290, A128549.
%K nonn
%O 1,2
%A _Hugo Pfoertner_, Jun 01 2024