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A136512 Produced by same formula that gives A093934 (signed tournaments), but with LCM instead of GCD in the exponent. 0
1, 2, 4, 12, 64, 616, 10304, 293744, 14381056, 1242433312, 196990542848, 59624929814720, 35242762808786944, 40573409794074305152, 89317952471536946659328, 368970766373159503907450624, 2827862662172992194150488080384, 40061570271801436240253461050024448, 1050869620561002649814192493096912289792 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

FORMULA

a(n) = Sum_{j} (1/(Product (k^(j_k) (j_k)!))) * 2^{t_j},

where j runs through all partitions of n into odd parts, say with j_1 parts of size 1, j_3 parts of size 3, etc.,

and t_j = (1/2)*[ Sum_{r=1..n, s=1..n} j_r j_s lcm(r,s) + Sum_{r} j_r ].

CROSSREFS

Sequence in context: A013202 A004400 A005831 * A137160 A013207 A172165

Adjacent sequences:  A136509 A136510 A136511 * A136513 A136514 A136515

KEYWORD

nonn

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com), Jul 21 2009

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Last modified February 16 04:18 EST 2012. Contains 205860 sequences.