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A245841 Triangle T read by rows: T(n,k) = Total number of odd parts in all partitions of n with at most k parts, 1 <= k <= n. 4

%I #14 Jul 21 2016 06:13:44

%S 1,0,2,1,2,5,0,2,4,8,1,3,7,10,15,0,4,8,14,18,24,1,4,12,19,27,32,39,0,

%T 4,12,24,34,44,50,58,1,5,18,32,49,62,74,81,90,0,6,18,40,60,82,98,112,

%U 120,130,1,6,24,49,81,108,135,154,170,179,190

%N Triangle T read by rows: T(n,k) = Total number of odd parts in all partitions of n with at most k parts, 1 <= k <= n.

%H Alois P. Heinz, <a href="/A245841/b245841.txt">Rows n = 1..141, flattened</a>

%e Triangle begins:

%e 1

%e 0 2

%e 1 2 5

%e 0 2 4 8

%e 1 3 7 10 15

%e 0 4 8 14 18 24

%e 1 4 12 19 27 32 39

%e 0 4 12 24 34 44 50 58

%e 1 5 18 32 49 62 74 81 90

%e 0 6 18 40 60 82 98 112 120 130

%e 1 6 24 49 81 108 135 154 170 179 190

%p b:= proc(n, i, k) option remember; `if`(n=0, [`if`(k=0, 1, 0), 0],

%p `if`(i<1 or k=0, [0$2], ((f, g)-> f+g+[0, `if`(irem(i, 2)=1,

%p g[1], 0)])(b(n, i-1, k), `if`(i>n, [0$2], b(n-i, i, k-1)))))

%p end:

%p T:= proc(n, k) T(n, k):= b(n$2, k)[2]+`if`(k=1, 0, T(n, k-1)) end:

%p seq(seq(T(n, k), k=1..n), n=1..14); # _Alois P. Heinz_, Aug 04 2014

%t Grid[Table[Sum[Sum[Count[Flatten[IntegerPartitions[n, {j}]], i], {i, 1, n, 2}], {j, k}], {n, 11}, {k, n}]]

%t (* second program: *)

%t b[n_, i_, k_] := b[n, i, k] = If[n == 0, {If[k == 0, 1, 0], 0}, If[i < 1 || k == 0, {0, 0}, Function[{f, g}, f + g + {0, If[Mod[i, 2] == 1, g[[1]], 0]}][b[n, i - 1, k], If[i > n, {0, 0}, b[n - i, i, k - 1]]]]];

%t T[n_, k_] := b[n, n, k][[2]];

%t Table[Table[T[n, k], {k, 1, n}] // Accumulate, {n, 1, 14}] // Flatten (* _Jean-François Alcover_, Jul 21 2016, after _Alois P. Heinz_ *)

%Y Partial sums of row entries of A245840.

%Y Cf. A066897 (outer diagonal).

%Y Cf. A245842, A245843.

%K nonn,tabl

%O 1,3

%A _L. Edson Jeffery_, Aug 03 2014

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Last modified April 24 04:02 EDT 2024. Contains 371918 sequences. (Running on oeis4.)