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A268870 Number of sequences in {1,...,n}^n with longest increasing subsequence of length three. 2
1, 45, 1131, 23611, 461154, 8837823, 169844455, 3307239364, 65559881608, 1325285983528, 27321430823064, 573932303529170, 12269791047231748, 266575464412874571, 5877527995117635663, 131334452330324176828, 2970563969803965041900, 67935408457473145627500 (list; graph; refs; listen; history; text; internal format)
OFFSET
3,2
LINKS
FORMULA
a(n) = A239299(n) - A239295(n).
EXAMPLE
a(3) = 1: 123.
a(4) = 45: 1123, 1124, 1134, 1213, 1214, 1223, 1224, 1231, 1232, 1233, 1241, 1242, 1243, 1244, 1314, 1323, 1324, 1334, 1341, 1342, 1343, 1344, 1423, 1424, 1434, 2123, 2124, 2134, 2234, 2314, 2324, 2334, 2341, 2342, 2343, 2344, 2434, 3123, 3124, 3134, 3234, 4123, 4124, 4134, 4234.
CROSSREFS
Column k=3 of A245667.
Sequence in context: A265615 A320363 A140346 * A049447 A327510 A215769
KEYWORD
nonn,easy
AUTHOR
Alois P. Heinz, Feb 15 2016
STATUS
approved

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Last modified March 28 11:59 EDT 2024. Contains 371254 sequences. (Running on oeis4.)