%I A140675
%S A140675 0,11,25,42,62,85,111,140,172,207,245,286,330,377,427,480,536,595,657,
%T A140675 722,790,861,935,1012,1092,1175,1261,1350,1442,1537,1635,1736,1840,1947,
%U A140675 2057,2170,2286,2405,2527,2652,2780,2911,3045,3182
%N A140675 n(3n+19)/2.
%F A140675 a(n)=(3*n^2 + 19*n)/2.
%F A140675 a(n)=3*n+a(n-1)+5 (with a(1)=0) [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it),
Nov 08 2009]
%e A140675 For n=2, a(2)=3*2+0+5=11; n=3, a(3)=3*3+11+5=25; n=4, a(4)=3*4+25+5=42
[From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Nov 08 2009]
%t A140675 s=0;lst={s};Do[s+=n++ +11;AppendTo[lst, s], {n, 0, 7!, 3}];lst [From
Vladimir Orlovsky (4vladimir(AT)gmail.com), Nov 19 2008]
%t A140675 Table[Sum[i + n - 3, {i, 7, n}], {n, 6, 52}] [From Zerinvary Lajos (zerinvarylajos(AT)yahoo.com),
Jul 11 2009]
%Y A140675 Cf. A000326, A005449, A045943, A115067, A140090, A140091, A059845, A140672,
A140673, A140674.
%Y A140675 The generalized pentagonal numbers b*n+3*n*(n-1)/2, for b = 1 through
12, form sequences A000326, A005449, A045943, A115067, A140090, A140091,
A059845, A140672, A140673, A140674, A140675, A151542.
%Y A140675 Sequence in context: A084547 A125868 A031025 this_sequence A161532 A118648
A105270
%Y A140675 Adjacent sequences: A140672 A140673 A140674 this_sequence A140676 A140677
A140678
%K A140675 easy,nonn
%O A140675 0,2
%A A140675 Omar E. Pol (info(AT)polprimos.com), May 22 2008
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