This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A375022 #24 Aug 06 2024 17:25:10 %S A375022 1,2,6,48,650,11604,253890,6572176,196467642,6660672060,252504829346, %T A375022 10584157180920,486052773276954,24267623565599428,1308816525199710210, %U A375022 75828568345500497184,4696852810090223180090,309727816544792336406156,21664419864179709448539042 %N A375022 Number of permutations of n (distinct) elements from [2n] without consecutive adjacent values. %H A375022 Alois P. Heinz, <a href="/A375022/b375022.txt">Table of n, a(n) for n = 0..366</a> %F A375022 a(n) = A338526(2n,n). %e A375022 a(0) = 1: the empty permutation. %e A375022 a(1) = 2: 1, 2. %e A375022 a(2) = 6: 13, 14, 24, 31, 41, 42. %e A375022 a(3) = 48: 135, 136, 142, 146, 152, 153, 162, 163, 164, 241, 246, 251, 253, 261, 263, 264, 314, 315, 316, 351, 352, 361, 362, 364, 413, 415, 416, 425, 426, 461, 462, 463, 513, 514, 516, 524, 526, 531, 536, 613, 614, 615, 624, 625, 631, 635, 641, 642. %Y A375022 Cf. A338526. %K A375022 nonn %O A375022 0,2 %A A375022 _Alois P. Heinz_, Aug 04 2024