A126799 - OEIS

A126799

Triangle read by rows, 1 <= m <= n: t(n,m) = gcd(s(n,m), S(n,m)), where s(n,m) is an unsigned Stirling number of the first kind and S(n,m) is a Stirling number of the second kind.

1, 1, 1, 1, 3, 1, 1, 1, 6, 1, 1, 5, 5, 10, 1, 1, 1, 45, 5, 15, 1, 1, 63, 7, 35, 35, 21, 1, 1, 1, 14, 7, 70, 14, 28, 1, 1, 3, 1, 42, 21, 378, 42, 36, 1, 1, 1, 30, 5, 14175, 21, 210, 30, 45, 1, 1, 33, 11, 2750, 110, 231, 231, 330, 165, 55, 1, 1, 1, 198, 11, 3630, 11, 462, 33, 1485, 55, 66, 1

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OFFSET

1,5

LINKS

Robert Israel, Table of n, a(n) for n = 1..10011 (rows 1 to 141, flattened)

EXAMPLE

Triangle starts:

1, 1;

1, 3, 1;

1, 1, 6, 1;

1, 5, 5, 10, 1;

1, 1, 45, 5, 15, 1;

MAPLE

with(combinat): T:=(n, k)->gcd(abs(stirling1(n, k)), stirling2(n, k)): for n from 1 to 13 do seq(T(n, k), k=1..n) od; # yields sequence in triangular form - Emeric Deutsch, Feb 25 2007

CROSSREFS

Cf. A008275, A008277, A128266 (row sums).

Sequence in context: A339768 A372644 A348954 * A135494 A367618 A016566

Adjacent sequences: A126796 A126797 A126798 * A126800 A126801 A126802

KEYWORD

nonn,tabl

AUTHOR

Leroy Quet, Feb 21 2007

EXTENSIONS

More terms from Emeric Deutsch, Feb 25 2007

STATUS

approved