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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, 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
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;
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
KEYWORD
nonn,tabl
AUTHOR
Leroy Quet, Feb 21 2007
EXTENSIONS
More terms from Emeric Deutsch, Feb 25 2007
STATUS
approved