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A235790 Triangle read by rows: T(n,k) = 2^k*A116608(n,k), n>=1, k>=1. 13
2, 4, 4, 4, 6, 8, 4, 20, 8, 24, 8, 4, 44, 16, 8, 52, 40, 6, 68, 80, 8, 88, 120, 16, 4, 108, 200, 32, 12, 116, 296, 80, 4, 148, 416, 160, 8, 176, 536, 320, 8, 176, 776, 480, 32, 10, 220, 936, 832, 64, 4, 236, 1232, 1232, 160, 12, 272, 1472, 1872, 320 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
It appears that T(n,k) is the number of overpartitions of n having k distinct parts. (This is true by definition, Joerg Arndt, Jan 20 2014).
Row n has length A003056(n) hence the first element of column k is in row A000217(k).
The first element of column k is A000079(k).
LINKS
EXAMPLE
Triangle begins:
2;
4;
4, 4;
6, 8;
4, 20;
8, 24, 8;
4, 44, 16;
8, 52, 40;
6, 68, 80;
8, 88, 120, 16;
4, 108, 200, 32;
12, 116, 296, 80;
4, 148, 416, 160;
8, 176, 536, 320;
8, 176, 776, 480, 32;
10, 220, 936, 832, 64;
4, 236, 1232, 1232, 160;
12, 272, 1472, 1872, 320;
4, 284, 1880, 2592, 640;
12, 324, 2216, 3632, 1152;
8, 328, 2704, 4944, 1856, 64;
...
MAPLE
b:= proc(n, i) option remember; `if`(n=0, 1, `if`(i<1, 0,
expand(b(n, i-1)+add(x*b(n-i*j, i-1), j=1..n/i))))
end:
T:= n->(p->seq(2^i*coeff(p, x, i), i=1..degree(p)))(b(n$2)):
seq(T(n), n=1..20); # Alois P. Heinz, Jan 20 2014
MATHEMATICA
b[n_, i_] := b[n, i] = If[n == 0, 1, If[i<1, 0, Expand[b[n, i-1] + Sum[x*b[n-i*j, i-1], {j, 1, n/i}]]]]; T[n_] := Function[p, Table[2^i * Coefficient[p, x, i], {i, 1, Exponent[p, x]}]][b[n, n]]; Table[T[n], {n, 1, 20}] // Flatten (* Jean-François Alcover, Oct 20 2016, after Alois P. Heinz *)
CROSSREFS
Row sums give A015128, n >= 1.
Column 1 is A062011.
Sequence in context: A307097 A050829 A033825 * A023988 A023819 A201629
KEYWORD
nonn,tabf,look
AUTHOR
Omar E. Pol, Jan 18 2014
STATUS
approved

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Last modified April 25 10:01 EDT 2024. Contains 371967 sequences. (Running on oeis4.)