%I #7 Dec 05 2013 19:56:18
%S 1,3,6,28,36,66,120,136,210,276,300,496,528,630,1176,2016,2080,3240,
%T 3570,4560,4950,5460,6216,8128,8256,9180,25200,29403,32640,32896,
%U 37128,39060,41328,41616,51040,61776,64980,73920,79800,93096,97020,103740,115440
%N Triangular numbers > 0 with a prime signature that has not occurred earlier.
%H Donovan Johnson, <a href="/A085076/b085076.txt">Table of n, a(n) for n = 1..1000</a>
%o (PARI) e=vector(22); for(j=1, 22, e[j]=concat(Str(j), ",")); ps=vector(1000); c=0; for(m=1, 7388415, t=m*(m+1)\2; om=omega(t); f=factorint(t); v=vector(om); for(j=1, om, v[j]=f[j, 2]); v=vecsort(v,,4); st=""; for(j=1, om, st=concat(st, e[v[j]])); fd=0; for(j=1, c, if(st==ps[j], fd=1; j=c)); if(fd==0, c++; write("b085076.txt", c " " t); ps[c]=st)) /* _Donovan Johnson_, May 26 2013 */
%K nonn
%O 1,2
%A _Amarnath Murthy_, Jul 01 2003
%E More terms from _David Wasserman_, Jan 14 2005
%E Offset corrected by _Donovan Johnson_, May 26 2013
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