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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.

A325548 Number of compositions of n with strictly decreasing differences.

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%I A325548 #17 Jan 27 2024 15:31:52
%S A325548 1,1,2,3,5,8,10,13,19,23,29,38,46,55,69,80,96,115,132,154,183,207,238,
%T A325548 276,314,356,405,455,513,579,647,724,809,897,998,1107,1225,1350,1486,
%U A325548 1639,1805,1973,2166,2374,2586,2824,3084,3346,3646,3964,4286,4655,5047
%N A325548 Number of compositions of n with strictly decreasing differences.
%C A325548 A composition of n is a finite sequence of positive integers summing to n.
%C A325548 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 A325548 Alois P. Heinz, <a href="/A325548/b325548.txt">Table of n, a(n) for n = 0..400</a>
%H A325548 Gus Wiseman, <a href="/A325325/a325325.txt">Sequences counting and ranking integer partitions by the differences of their successive parts.</a>
%e A325548 The a(1) = 1 through a(8) = 19 compositions:
%e A325548   (1)  (2)   (3)   (4)    (5)    (6)     (7)    (8)
%e A325548        (11)  (12)  (13)   (14)   (15)    (16)   (17)
%e A325548              (21)  (22)   (23)   (24)    (25)   (26)
%e A325548                    (31)   (32)   (33)    (34)   (35)
%e A325548                    (121)  (41)   (42)    (43)   (44)
%e A325548                           (122)  (51)    (52)   (53)
%e A325548                           (131)  (132)   (61)   (62)
%e A325548                           (221)  (141)   (133)  (71)
%e A325548                                  (231)   (142)  (134)
%e A325548                                  (1221)  (151)  (143)
%e A325548                                          (232)  (152)
%e A325548                                          (241)  (161)
%e A325548                                          (331)  (233)
%e A325548                                                 (242)
%e A325548                                                 (251)
%e A325548                                                 (332)
%e A325548                                                 (341)
%e A325548                                                 (431)
%e A325548                                                 (1331)
%p A325548 b:= proc(n, l, d) option remember; `if`(n=0, 1, add(`if`(l=0 or
%p A325548        j-l<d, b(n-j, j, `if`(l=0, infinity, j-l)), 0), j=1..n))
%p A325548     end:
%p A325548 a:= n-> b(n, 0$2):
%p A325548 seq(a(n), n=0..52);  # _Alois P. Heinz_, Jan 27 2024
%t A325548 Table[Length[Select[Join@@Permutations/@IntegerPartitions[n],Greater@@Differences[#]&]],{n,0,15}]
%Y A325548 Cf. A011782, A000740, A008965, A070211, A175342, A179254, A320470, A325457, A325545, A325546, A325547, A325552, A325557.
%K A325548 nonn
%O A325548 0,3
%A A325548 _Gus Wiseman_, May 10 2019
%E A325548 a(26)-a(44) from _Lars Blomberg_, May 30 2019
%E A325548 a(45)-a(52) from _Alois P. Heinz_, Jan 27 2024