%I A001267 M4550 N1934
%S A001267 0,0,0,0,1,8,60,444,3599,32484,325322,3582600,43029621,559774736,7841128936,
%T A001267 117668021988,1883347579515,32026067455084,576605574327174,10957672400252944,
%U A001267 219190037987444577,4603645435776504120,101292568208941883236,2329975164242735146316
%N A001267 One-half the number of permutations of length n with exactly 3 rising
or falling successions.
%C A001267 (1/2) times number of permutations of 12...n such that exactly 3 of the
following occur: 12, 23, ..., (n-1)n, 21, 32, ..., n(n-1).
%D A001267 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences,
Academic Press, 1995 (includes this sequence).
%D A001267 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973
(includes this sequence).
%D A001267 F. N. David, M. G. Kendall and D. E. Barton, Symmetric Function and Allied
Tables, Cambridge, 1966, p. 263.
%D A001267 J. Riordan, A recurrence for permutations without rising or falling successions.
Ann. Math. Statist. 36 (1965), 708-710.
%F A001267 Coefficient of t^3 in S[n](t) defined in A002464, divided by 2.
%Y A001267 Cf. A002464, A000130, A086852. Equals A086854/2. A diagonal of A010028.
%Y A001267 Sequence in context: A093132 A094169 A129325 this_sequence A099156 A129331
A005990
%Y A001267 Adjacent sequences: A001264 A001265 A001266 this_sequence A001268 A001269
A001270
%K A001267 nonn
%O A001267 0,6
%A A001267 N. J. A. Sloane (njas(AT)research.att.com).
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