%I A086855
%S A086855 0,0,0,0,0,2,22,226,2198,22120,236968,2732268,33940644,453148422,6480322210,
%T A086855 98907371822,1605581578202,27631315113916,502618772515748,9637245372790760,
%U A086855 194291040277517688,4109014039030693578,90968013940830446574,2104072961763468757082
%N A086855 Number of permutations of length n with exactly 4 rising or falling successions.
%C A086855 Permutations of 12...n such that exactly 4 of the following occur: 12,
23, ..., (n-1)n, 21, 32, ..., n(n-1).
%D A086855 F. N. David, M. G. Kendall and D. E. Barton, Symmetric Function and Allied
Tables, Cambridge, 1966, p. 263.
%D A086855 J. Riordan, A recurrence for permutations without rising or falling successions.
Ann. Math. Statist. 36 (1965), 708-710.
%F A086855 Coefficient of t^4 in S[n](t) defined in A002464.
%Y A086855 Cf. A002464, A000130, A000349, A001267, A086852, A086853. A diagonal
of A001100.
%Y A086855 Twice A001268.
%Y A086855 Sequence in context: A137109 A002276 A112893 this_sequence A089182 A138140
A151617
%Y A086855 Adjacent sequences: A086852 A086853 A086854 this_sequence A086856 A086857
A086858
%K A086855 nonn
%O A086855 0,6
%A A086855 N. J. A. Sloane (njas(AT)research.att.com), Aug 19 2003
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