a(n) = 5a(n-1) - 5a(n-2) + a(n-3) with a(1) = 1 and a(k) = 0 if k <= 0.
0, 1, 5, 20, 76, 285, 1065, 3976, 14840, 55385, 206701, 771420, 2878980, 10744501
5 seqfan posts
Fri Jun 24 08:36:06 CEST 2011 [seqfan] Re: three triangular numbers in a row
Fri Jun 24 08:31:20 CEST 2011 [seqfan] Re: three triangular numbers in a row
Fri Jun 24 06:35:59 CEST 2011 [seqfan] Re: three triangular numbers in a row
Fri Jun 24 06:34:52 CEST 2011 [seqfan] Re: three triangular numbers in a row
Fri Jun 24 05:58:37 CEST 2011 [seqfan] three triangular numbers in a row
Index of A-numbers in seqfan: by ascending order
by month
by frequency
by keyword
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