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A136394 Triangle read by rows: T(n,k) is the number of permutations of an n-set having k cycles of size > 1 (0<=k<=floor(n/2)). 1
1, 1, 1, 1, 1, 5, 1, 20, 3, 1, 84, 35, 1, 409, 295, 15, 1, 2365, 2359, 315, 1, 16064, 19670, 4480, 105, 1, 125664, 177078, 56672, 3465, 1, 1112073, 1738326, 703430, 74025, 945, 1, 10976173, 18607446, 8941790, 1346345, 45045, 1, 119481284, 216400569, 118685336 (list; graph; refs; listen; history; internal format)
OFFSET

0,6

LINKS

Alois P. Heinz, Table of n, a(n) for n = 0..675

FORMULA

E.g.f.: exp(x*(1-y))/(1-x)^y. Binomial transform of triangle A008306. exp(x)*((-x-ln(1-x))^k)/k! is e.g.f. of k-th column.

EXAMPLE

1;

1;

1,1;

1,5;

1,20,3;

1,84,35;

1,409,295,15;

1,2365,2359,315;

MAPLE

egf := proc(k::nonnegint) option remember; x-> exp(x)* ((-x-ln(1-x))^k)/k! end; T := (n, k)-> coeff (series (egf(k)(x), x=0, n+1), x, n) *n!; seq (seq (T(n, k), k=0..floor(n/2)), n=0..30); [From Alois P. Heinz (heinz(AT)hs-heilbronn.de), Aug 14 2008]

CROSSREFS

Cf. A006231(first column), A000276, A000483, A124324.

Sequence in context: A147437 A147369 A066480 * A145372 A145373 A088577

Adjacent sequences:  A136391 A136392 A136393 * A136395 A136396 A136397

KEYWORD

easy,nonn,tabf

AUTHOR

Vladeta Jovovic (vladeta(AT)eunet.rs), May 03 2008

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Last modified February 15 19:09 EST 2012. Contains 205852 sequences.