Search: id:A077003 Results 1-1 of 1 results found. %I A077003 %S A077003 1,1,1,2,4,9,22,59,167,501,1585,5258,18215,65676,245738,951740,3806961, %T A077003 15696503,66594623,290279233,1298168196,5948954024,27903067710, %U A077003 133818411722,655573653819,3277868269096,16713914267109,86848046111951 %N A077003 a(n)= index of triangular number A077002(n). %p A077003 a[1] := 1:b[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)):b[n] := a[n]:a[n] := a[n]*(a[n]+1)/ 2:od:seq(b[l],l=1..100); %Y A077003 Cf. A077002. %Y A077003 Sequence in context: A092920 A035053 A000571 this_sequence A046917 A159329 A159334 %Y A077003 Adjacent sequences: A077000 A077001 A077002 this_sequence A077004 A077005 A077006 %K A077003 nonn %O A077003 1,4 %A A077003 Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Oct 26 2002 %E A077003 More terms from Sascha Kurz (sascha.kurz(AT)uni-bayreuth.de), Jan 26 2003 Search completed in 0.001 seconds