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%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
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