Euler or up/down numbers: e.g.f. sec(x) + tan(x). Also number of alternating permutations on n letters.
1, 1, 1, 2, 5, 16, 61, 272, 1385, 7936, 50521, 353792, 2702765, 22368256
Index of A-numbers in seqfan: by ascending order
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14 seqfan posts
Mon Nov 28 01:53:03 CET 2011 [seqfan] Help needed with triangle related to new sequence
Wed Jan 26 15:24:23 CET 2011 [seqfan] Experiment: period of a(n) mod p (after ditching rational expressions and linear recurrences)
Fri Oct 29 05:35:16 CEST 2010 [seqfan] Implementing first 500 sequences in Java
Fri Sep 3 09:31:22 CEST 2010 [seqfan] Re: zig-zag pseudoprimes
Thu Sep 2 15:12:42 CEST 2010 [seqfan] Re: zig-zg pseudoprimes
Thu Sep 2 14:47:03 CEST 2010 [seqfan] Re: zig-zag pseudoprimes
Thu Sep 2 14:19:28 CEST 2010 [seqfan] Re: zig-zag pseudoprimes
Wed Sep 1 20:17:55 CEST 2010 [seqfan] Re: zig-zag pseudoprimes
Wed Sep 1 16:54:43 CEST 2010 [seqfan] Re: zig-zag pseudoprimes
Wed Sep 1 16:19:27 CEST 2010 [seqfan] Re: zig-zag pseudoprimes
Wed Sep 1 12:54:33 CEST 2010 [seqfan] Re: zig-zag pseudoprimes
Wed Sep 1 09:55:20 CEST 2010 [seqfan] "zig-zag pseudoprimes"
Mon Oct 26 12:03:22 CET 2009 [seqfan] Re: A metric and UI for Pandora-like OEIS exploration
Mon Oct 26 11:03:39 CET 2009 [seqfan] A metric and UI for Pandora-like OEIS exploration
Index of A-numbers in seqfan: by ascending order
by month
by frequency
by keyword
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