# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a325545 Showing 1-1 of 1 %I A325545 #14 Feb 20 2022 20:28:41 %S A325545 1,1,2,3,7,13,17,34,59,105,166,279,442,730,1157,1927,3045,4741,7527, %T A325545 11667,18048,27928,43334,65861,101385,153404,232287,347643,523721, %U A325545 780083,1165331,1725966,2561625,3773838,5561577,8151209,11920717,17364461,25269939,36635775 %N A325545 Number of compositions of n with distinct differences. %C A325545 A composition of n is a finite sequence of positive integers summing to n. %C A325545 The differences of a sequence are defined as if the sequence were increasing, so for example the differences of (3,1,2) are (-2,1). %H A325545 Fausto A. C. Cariboni, Table of n, a(n) for n = 0..70 %H A325545 Gus Wiseman, Sequences counting and ranking integer partitions by the differences of their successive parts. %e A325545 The a(1) = 1 through a(6) = 17 compositions: %e A325545 (1) (2) (3) (4) (5) (6) %e A325545 (11) (12) (13) (14) (15) %e A325545 (21) (22) (23) (24) %e A325545 (31) (32) (33) %e A325545 (112) (41) (42) %e A325545 (121) (113) (51) %e A325545 (211) (122) (114) %e A325545 (131) (132) %e A325545 (212) (141) %e A325545 (221) (213) %e A325545 (311) (231) %e A325545 (1121) (312) %e A325545 (1211) (411) %e A325545 (1131) %e A325545 (1221) %e A325545 (1311) %e A325545 (2112) %t A325545 Table[Length[Select[Join@@Permutations/@IntegerPartitions[n],UnsameQ@@Differences[#]&]],{n,0,15}] %Y A325545 Cf. A000079, A000740, A008965, A059966, A070211, A175342, A242882, A325325, A325352, A325546, A325547, A325548, A325551, A325554. %K A325545 nonn %O A325545 0,3 %A A325545 _Gus Wiseman_, May 10 2019 %E A325545 More terms from _Alois P. Heinz_, May 11 2019 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE