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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.

A357704 Triangle read by rows where T(n,k) is the number of reversed integer partitions of n with half-alternating sum k, where k ranges from -n to n in steps of 2.

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%I A357704 #7 Oct 10 2022 20:47:12
%S A357704 1,0,1,0,0,2,0,0,1,2,0,0,2,0,3,0,0,2,2,0,3,0,0,3,1,3,0,4,0,0,3,2,4,2,
%T A357704 0,4,0,0,4,2,6,2,3,0,5,0,0,4,3,5,7,3,3,0,5,0,0,5,3,8,4,10,2,4,0,6,0,0,
%U A357704 5,4,8,6,11,9,3,4,0,6,0,0,6,4,11,5,15,8,13,3,5,0,7
%N A357704 Triangle read by rows where T(n,k) is the number of reversed integer partitions of n with half-alternating sum k, where k ranges from -n to n in steps of 2.
%C A357704 We define the half-alternating sum of a sequence (A, B, C, D, E, F, G, ...) to be A + B - C - D + E + F - G - ...
%e A357704 Triangle begins:
%e A357704   1
%e A357704   0  1
%e A357704   0  0  2
%e A357704   0  0  1  2
%e A357704   0  0  2  0  3
%e A357704   0  0  2  2  0  3
%e A357704   0  0  3  1  3  0  4
%e A357704   0  0  3  2  4  2  0  4
%e A357704   0  0  4  2  6  2  3  0  5
%e A357704   0  0  4  3  5  7  3  3  0  5
%e A357704   0  0  5  3  8  4 10  2  4  0  6
%e A357704   0  0  5  4  8  6 11  9  3  4  0  6
%e A357704   0  0  6  4 11  5 15  8 13  3  5  0  7
%e A357704   0  0  6  5 11  8 13 19 10 13  4  5  0  7
%e A357704   0  0  7  5 14  8 19 13 25  9 17  4  6  0  8
%e A357704   0  0  7  6 14 11 19 17 29 23 13 18  5  6  0  8
%e A357704 Row n = 7 counts the following reversed partitions:
%e A357704   .  .  (115)   (124)   (133)      (11113)   .  (7)
%e A357704         (1114)  (1222)  (223)      (111112)     (16)
%e A357704         (1123)          (11122)                 (25)
%e A357704                         (1111111)               (34)
%t A357704 halfats[f_]:=Sum[f[[i]]*(-1)^(1+Ceiling[i/2]),{i,Length[f]}];
%t A357704 Table[Length[Select[Reverse/@IntegerPartitions[n],halfats[#]==k&]],{n,0,15},{k,-n,n,2}]
%Y A357704 Row sums are A000041.
%Y A357704 Last entry of row n is A008619(n).
%Y A357704 The central column in the non-reverse case is A035363, skew A035544.
%Y A357704 For original reverse-alternating sum we have A344612.
%Y A357704 For original alternating sum we have A344651, ordered A097805.
%Y A357704 The non-reverse version is A357637, skew A357638.
%Y A357704 The central column is A357639, skew A357640.
%Y A357704 The non-reverse ordered version (compositions) is A357645, skew A357646.
%Y A357704 The skew-alternating version is A357705.
%Y A357704 A351005 = alternately equal and unequal partitions, compositions A357643.
%Y A357704 A351006 = alternately unequal and equal partitions, compositions A357644.
%Y A357704 A357621 gives half-alternating sum of standard compositions, skew A357623.
%Y A357704 A357629 gives half-alternating sum of prime indices, skew A357630.
%Y A357704 A357633 gives half-alternating sum of Heinz partition, skew  A357634.
%Y A357704 Cf. A029862, A053251, A357136, A357189, A357487, A357488, A357631, A357632, A357641.
%K A357704 nonn,tabl
%O A357704 0,6
%A A357704 _Gus Wiseman_, Oct 10 2022