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Number of permutations of [n] with exactly two (possibly overlapping) occurrences of the consecutive pattern 1324.
2

%I #9 Nov 09 2015 08:12:04

%S 2,29,407,5856,84351,1251246,19318314,311306106,5247587002,

%T 92593553775,1709675651881,33009644160452,665774603385155,

%U 14011066071814409,307285854478257587,7014599706534263680,166463062283304010885,4101715354110043233880,104819153609360857542346

%N Number of permutations of [n] with exactly two (possibly overlapping) occurrences of the consecutive pattern 1324.

%H Alois P. Heinz, <a href="/A264175/b264175.txt">Table of n, a(n) for n = 6..200</a>

%e a(6) = 2: 132546, 142536.

%e a(7) = 29: 1243657, 1253647, 1324657, 1325467, 1325476, 1326475, 1326574, 1425367, 1425376, 1426375, 1426573, 1436572, 1526374, 1526473, 1536472, 2143657, 2153647, 2436571, 2536471, 3142657, 3152647, 4132657, 4152637, 5132647, 5142637, 6132547, 6142537, 7132546, 7142536.

%Y Column k=2 of A264173.

%K nonn

%O 6,1

%A _Alois P. Heinz_, Nov 06 2015