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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.

A325875 Number of compositions of n whose differences of all degrees > 1 are nonzero.

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%I A325875 #5 Jun 02 2019 23:40:14
%S A325875 1,1,2,3,7,13,20,38,69,129,222,407,726,1313,2318,4146,7432,13296,
%T A325875 23759,42458,75714
%N A325875 Number of compositions of n whose differences of all degrees > 1 are nonzero.
%C A325875 The differences of a sequence are defined as if the sequence were increasing, so for example the differences of (6,3,1) are (-3,-2). The zeroth differences are the sequence itself, while k-th differences for k > 0 are the differences of the (k-1)-th differences. If m is the length of the sequence, its differences of all degrees are the union of the zeroth through m-th differences.
%C A325875 A composition of n is a finite sequence of positive integers with sum n.
%C A325875 The case for all degrees including 1 is A325851.
%H A325875 Gus Wiseman, <a href="/A325325/a325325.txt">Sequences counting and ranking integer partitions by the differences of their successive parts</a>
%e A325875 The a(1) = 1 through a(6) = 20 compositions:
%e A325875   (1)  (2)   (3)   (4)    (5)     (6)
%e A325875        (11)  (12)  (13)   (14)    (15)
%e A325875              (21)  (22)   (23)    (24)
%e A325875                    (31)   (32)    (33)
%e A325875                    (112)  (41)    (42)
%e A325875                    (121)  (113)   (51)
%e A325875                    (211)  (122)   (114)
%e A325875                           (131)   (132)
%e A325875                           (212)   (141)
%e A325875                           (221)   (213)
%e A325875                           (311)   (231)
%e A325875                           (1121)  (312)
%e A325875                           (1211)  (411)
%e A325875                                   (1122)
%e A325875                                   (1131)
%e A325875                                   (1212)
%e A325875                                   (1311)
%e A325875                                   (2121)
%e A325875                                   (2211)
%e A325875                                   (11211)
%t A325875 Table[Length[Select[Join@@Permutations/@IntegerPartitions[n],!MemberQ[Union@@Table[Differences[#,i],{i,2,Length[#]}],0]&]],{n,0,10}]
%Y A325875 Cf. A049988, A238423, A325325, A325468, A325545, A325849, A325850, A325851, A325852, A325874, A325876.
%K A325875 nonn,more
%O A325875 0,3
%A A325875 _Gus Wiseman_, Jun 02 2019