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A128266 a(n) = Sum_{m=1..n} 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, 2, 5, 9, 22, 68, 163, 136, 525, 14519, 3918, 5954, 26561, 23897, 875479, 464545, 303146, 1576515, 15328385, 1297494, 25992621, 92698823, 64096034, 31484634, 16667307085, 737157766, 397339059223, 115011291216, 30816653208, 4304179162 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..30.

MAPLE

with(combinat): T:=(n, k)->gcd(abs(stirling1(n, k)), stirling2(n, k)): seq(add(T(n, k), k=1..n), n=1..35); # Emeric Deutsch, Feb 25 2007

CROSSREFS

Sequence in context: A173565 A268651 A002935 * A088356 A246350 A192477

Adjacent sequences:  A128263 A128264 A128265 * A128267 A128268 A128269

KEYWORD

nonn

AUTHOR

Leroy Quet, Feb 22 2007

EXTENSIONS

More terms from Emeric Deutsch, Feb 25 2007

STATUS

approved

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Last modified August 12 16:40 EDT 2020. Contains 336439 sequences. (Running on oeis4.)