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 A356604 #10 Sep 01 2022 19:48:14 %S A356604 1,1,1,1,3,4,5,9,13,24,40,61,101,160,257,415,679,1103,1774,2884,4656, %T A356604 7517,12165,19653,31753,51390,83134,134412,217505,351814,569081, %U A356604 920769,1489587,2409992,3899347,6309059,10208628,16518910,26729830,43254212,69994082 %N A356604 Number of integer compositions of n into odd parts covering an initial interval of odd positive integers. %e A356604 The a(1) = 1 through a(8) = 13 compositions: %e A356604 (1) (11) (111) (13) (113) (1113) (133) (1133) %e A356604 (31) (131) (1131) (313) (1313) %e A356604 (1111) (311) (1311) (331) (1331) %e A356604 (11111) (3111) (11113) (3113) %e A356604 (111111) (11131) (3131) %e A356604 (11311) (3311) %e A356604 (13111) (111113) %e A356604 (31111) (111131) %e A356604 (1111111) (111311) %e A356604 (113111) %e A356604 (131111) %e A356604 (311111) %e A356604 (11111111) %e A356604 The a(9) = 24 compositions: %e A356604 (135) (11133) (1111113) (111111111) %e A356604 (153) (11313) (1111131) %e A356604 (315) (11331) (1111311) %e A356604 (351) (13113) (1113111) %e A356604 (513) (13131) (1131111) %e A356604 (531) (13311) (1311111) %e A356604 (31113) (3111111) %e A356604 (31131) %e A356604 (31311) %e A356604 (33111) %t A356604 normQ[m_]:=Or[m=={},Union[m]==Range[Max[m]]]; %t A356604 Table[Length[Select[Join@@Permutations/@IntegerPartitions[n],normQ[(#+1)/2]&]],{n,0,15}] %Y A356604 The case of partitions is A053251, ranked by A356232 and A356603. %Y A356604 These compositions are ranked by the intersection of A060142 and A333217. %Y A356604 This is the odd initial case of A107428. %Y A356604 This is the odd restriction of A107429. %Y A356604 This is the normal/covering case of A324969 (essentially A000045). %Y A356604 The non-initial version is A356605. %Y A356604 A000041 counts partitions, compositions A011782. %Y A356604 A055932 lists numbers with prime indices covering an initial interval. %Y A356604 A066208 lists numbers with all odd prime indices, counted by A000009. %Y A356604 Cf. A001221, A001222, A001227, A005408, A061395, A066205, A073493, A137921, A356224. %K A356604 nonn %O A356604 0,5 %A A356604 _Gus Wiseman_, Aug 30 2022 %E A356604 More terms from _Alois P. Heinz_, Sep 01 2022