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 A246323 Triangle read by rows: T(n,k) = number of normal planar lambda terms of size n with k free variables (n >= 1, 1 <= k <= n). 1
 1, 2, 1, 9, 6, 2, 54, 40, 20, 5, 378, 295, 175, 70, 14, 2916, 2346, 1526, 756, 252, 42, 24057, 19739, 13587, 7602, 3234, 924, 132, 208494, 173426, 123978, 74964, 36828, 13728, 3432, 429 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Noam Zeilberger, Alain Giorgetti, A correspondence between rooted planar maps and normal planar lambda terms, arXiv:1408.5028 [cs.LO], 2014. EXAMPLE Triangle begins: 1 2,1 9,6,2 54,40,20,5 378,295,175,70,14 2916,2346,1526,756,252,42 24057,19739,13587,7602,3234,924,132, 208494,173426,123978,74964,36828,13728,3432,429 ... CROSSREFS Cf. A000108, A000984, A000168, A246322. Sequence in context: A235595 A061356 A141028 * A201685 A120671 A245461 Adjacent sequences:  A246320 A246321 A246322 * A246324 A246325 A246326 KEYWORD nonn,tabl AUTHOR N. J. A. Sloane, Aug 28 2014 STATUS approved

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Last modified February 28 09:38 EST 2020. Contains 332323 sequences. (Running on oeis4.)