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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.

A342342 Number of strict compositions of n with all adjacent parts (x, y) satisfying x <= 2y and y <= 2x.

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%I A342342 #8 May 24 2021 06:41:42
%S A342342 1,1,1,3,1,3,5,5,3,11,9,11,17,15,29,39,31,39,65,57,107,127,149,155,
%T A342342 187,265,293,419,523,571,781,763,941,1371,1387,2125,2383,2775,3243,
%U A342342 4189,4555,5349,7241,7997,10591,13171,14581,17213,20253,25177,27701,34317
%N A342342 Number of strict compositions of n with all adjacent parts (x, y) satisfying x <= 2y and y <= 2x.
%C A342342 Each quotient of adjacent parts is between 1/2 and 2 inclusive.
%e A342342 The a(1) = 1 through a(12) = 17 strict compositions (A = 10, B = 11, C = 12):
%e A342342   1   2   3    4   5    6     7     8    9     A      B      C
%e A342342           12       23   24    34    35   36    46     47     48
%e A342342           21       32   42    43    53   45    64     56     57
%e A342342                         123   124        54    235    65     75
%e A342342                         321   421        63    532    74     84
%e A342342                                          234   1234   236    246
%e A342342                                          243   1243   245    345
%e A342342                                          324   3421   542    354
%e A342342                                          342   4321   632    435
%e A342342                                          423          1235   453
%e A342342                                          432          5321   534
%e A342342                                                              543
%e A342342                                                              642
%e A342342                                                              1236
%e A342342                                                              1245
%e A342342                                                              5421
%e A342342                                                              6321
%t A342342 Table[Length[Select[Join@@Permutations/@Select[IntegerPartitions[n],UnsameQ@@#&],And@@Table[#[[i]]<=2*#[[i-1]]&&#[[i-1]]<=2*#[[i]],{i,2,Length[#]}]&]],{n,0,15}]
%Y A342342 The non-strict version is A224957.
%Y A342342 The case with strict relations is A342341 (non-strict: A342330).
%Y A342342 A000929 counts partitions with adjacent parts x >= 2y.
%Y A342342 A002843 counts compositions with adjacent parts x <= 2y.
%Y A342342 A154402 counts partitions with adjacent parts x = 2y.
%Y A342342 A274199 counts compositions with adjacent parts x < 2y.
%Y A342342 A342094 counts partitions with adjacent x <= 2y (strict: A342095).
%Y A342342 A342096 counts partitions without adjacent x >= 2y (strict: A342097).
%Y A342342 A342098 counts partitions with adjacent parts x > 2y.
%Y A342342 A342331 counts compositions with adjacent parts x = 2y or y = 2x.
%Y A342342 A342332 counts compositions with adjacent parts x > 2y or y > 2x.
%Y A342342 A342333 counts compositions with adjacent parts x >= 2y or y >= 2x.
%Y A342342 A342335 counts compositions with adjacent parts x >= 2y or y = 2x.
%Y A342342 A342337 counts partitions with adjacent parts x = y or x = 2y.
%Y A342342 A342338 counts compositions with adjacent parts x < 2y and y <= 2x.
%Y A342342 Cf. A003114, A003242, A034296, A167606, A342083, A342084, A342087, A342191, A342334, A342336, A342340.
%K A342342 nonn
%O A342342 0,4
%A A342342 _Gus Wiseman_, Mar 12 2021
%E A342342 a(40)-a(51) from _Alois P. Heinz_, May 24 2021