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 A350840 #10 Jan 27 2022 20:46:22 %S A350840 1,1,1,1,2,3,2,4,5,6,7,8,10,13,17,19,22,25,30,35,43,52,60,70,81,93, %T A350840 106,122,142,166,190,216,249,287,325,371,420,479,543,617,695,784,888, %U A350840 1000,1126,1266,1420,1594,1792,2008,2247,2514,2809,3135,3496,3891,4332 %N A350840 Number of strict integer partitions of n with no adjacent parts of quotient 2. %e A350840 The a(1) = 1 through a(13) = 13 partitions (A..D = 10..13): %e A350840 1 2 3 4 5 6 7 8 9 A B C D %e A350840 31 32 51 43 53 54 64 65 75 76 %e A350840 41 52 62 72 73 74 93 85 %e A350840 61 71 81 82 83 A2 94 %e A350840 431 432 91 92 B1 A3 %e A350840 531 532 A1 543 B2 %e A350840 541 641 651 C1 %e A350840 731 732 643 %e A350840 741 652 %e A350840 831 751 %e A350840 832 %e A350840 931 %e A350840 5431 %t A350840 Table[Length[Select[IntegerPartitions[n],UnsameQ@@#&&And@@Table[#[[i-1]]/#[[i]]!=2,{i,2,Length[#]}]&]],{n,0,30}] %Y A350840 The version for subsets of prescribed maximum is A045691. %Y A350840 The double-free case is A120641. %Y A350840 The non-strict case is A350837, ranked by A350838. %Y A350840 An additive version (differences) is A350844, non-strict A350842. %Y A350840 The non-strict complement is counted by A350846, ranked by A350845. %Y A350840 Versions for prescribed quotients: %Y A350840 = 2: A154402, sets A001511. %Y A350840 != 2: A350840 (this sequence), sets A045691. %Y A350840 >= 2: A000929, sets A018819. %Y A350840 <= 2: A342095, non-strict A342094. %Y A350840 < 2: A342097, non-strict A342096, sets A045690. %Y A350840 > 2: A342098, sets A040039. %Y A350840 A000041 = integer partitions. %Y A350840 A000045 = sets containing n with all differences > 2. %Y A350840 A003114 = strict partitions with no successions, ranked by A325160. %Y A350840 A116931 = partitions with no successions, ranked by A319630. %Y A350840 A116932 = partitions with differences != 1 or 2, strict A025157. %Y A350840 A323092 = double-free integer partitions, ranked by A320340. %Y A350840 A350839 = partitions with gaps and conjugate gaps, ranked by A350841. %Y A350840 Cf. A003000, A018819, A303362, A323093, A323094, A337135, A342191. %K A350840 nonn %O A350840 0,5 %A A350840 _Gus Wiseman_, Jan 20 2022