A167128 Triangle T(m,n) read by rows: T(m,n) = Sum_{k=1..n} StirlingS2(m, n) * StirlingS2(m, k).

1, 1, 2, 1, 12, 5, 1, 56, 84, 15, 1, 240, 1025, 510, 52, 1, 992, 10980, 12155, 3030, 203, 1, 4032, 109865, 250250, 119700, 18396, 877, 1, 16256, 1056804, 4754295, 4037250, 1093526, 115892, 4140, 1, 65280, 9925025, 85866270, 125131902, 54634608

Offset

1,3

Comments

Row sums are: {1, 3, 18, 156, 1828, 27361, 503121, 11078164, 286158309, 8532624076,...}

Links

G. C. Greubel, Table of n, a(n) for the first 50 rows

Example

{1},
{1, 2},
{1, 12, 5},
{1, 56, 84, 15},
{1, 240, 1025, 510, 52},
{1, 992, 10980, 12155, 3030, 203},
{1, 4032, 109865, 250250, 119700, 18396, 877},
{1, 16256, 1056804, 4754295, 4037250, 1093526, 115892, 4140},
{1, 65280, 9925025, 85866270, 125131902, 54634608, 9752820, 761256, 21147},
{1, 261632, 91825860, 1498812435, 3677221800, 2494968273, 677252520, 86946750, 5218830, 115975}

Mathematica

T[m_, n_] = Sum[StirlingS2[m, n]*StirlingS2[m, k], {k, 1, n}];
Flatten[Table[Table[T[m, n], {n, 1, m}], {m, 1, 10}]]

Crossrefs

Sequence in context: A107722 A357013 A370552 * A332749 A342430 A181417

Adjacent sequences: A167125 A167126 A167127 * A167129 A167130 A167131

Keyword

nonn,tabl

Author

Roger L. Bagula, Oct 28 2009

Extensions

Edited by the OEIS editors, Jun 05 2016

Status

approved