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%I #10 Jun 04 2021 15:06:18
%S 1,1,1,3,10,45,253,1770,14028,125751,1256905,13825911,165902220,
%T 2156701326,30193705191,452904989670,7246477931241,123190111062756,
%U 2217421939553376,42131016700673761,842620333202031306
%N a(1) = 1, a(n+1) is the largest triangular number <= n*a(n).
%H Harvey P. Dale, <a href="/A077002/b077002.txt">Table of n, a(n) for n = 1..451</a>
%p a[1] := 1:for n from 2 to 100 do a[n] := floor(evalf(-1/2+1/2*sqrt(1+8*(n-1)*a[n-1])+1/10^50,300)):a[n] := a[n]*(a[n]+1)/2:od:seq(a[l],l=1..100);
%t nxt[{n_,a_}]:=Module[{c=Floor[(Sqrt[1+8n*a]-1)/2]},{n+1,(c(c+1))/2}]; NestList[nxt,{1,1},20][[All,2]] (* _Harvey P. Dale_, Jun 04 2021 *)
%Y Cf. A077003.
%K nonn
%O 1,4
%A _Amarnath Murthy_, Oct 26 2002
%E More terms from _Sascha Kurz_, Jan 26 2003
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