G.f.: (1+x)/(1-3*x).
1, 4, 12, 36, 108, 324, 972, 2916, 8748, 26244, 78732, 236196, 708588, 2125764
3 seqfan posts
Sun Sep 13 18:42:04 CEST 2009 [seqfan] Re: Duplicates
Thu Aug 13 14:39:45 CEST 2009 [seqfan] Re: Rant on Maple code
Thu Aug 13 08:22:53 CEST 2009 [seqfan] Re: Rant on Maple code
Index of A-numbers in seqfan: by ascending order
by month
by frequency
by keyword
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