%I A140354
%S A140354 1,20,220,1760,11440,64064,320320,1464320,6223360,24893440,94595072,
%T A140354 343982080,1203937280,4074864640,13388840960,42844291072,133888409600,
%U A140354 409541017600,1228623052800,3621204787200,10501493882880,30004268236800
%N A140354 Binomial(n+9,9)*2^n.
%C A140354 With a different offset, number of n-permutations (n>=9) of 3 objects:
u, v, z with repetition allowed, containing exactly nine (9) u's.
%C A140354 If n=9 then a(0)= 1
%C A140354 Example: a(1)=20 because we have
%C A140354 uuuuuuuuuv, uuuuuuuuvu, uuuuuuuvuu, uuuuuuvuuu, uuuuuvuuuu, uuuuvuuuuu,
uuuvuuuuuu, uuvuuuuuuu, uvuuuuuuuu, vuuuuuuuuu, uuuuuuuuuz, uuuuuuuuzu,
uuuuuuuzuu, uuuuuuzuuu, uuuuuzuuuu, uuuuzuuuuu, uuuzuuuuuu, uuzuuuuuuu,
uzuuuuuuuu and zuuuuuuuuu.
%p A140354 seq(binomial(n+9,9)*2^n,n=0..23);
%o A140354 (Other) SAGE: [lucas_number2(n, 2, 0)*binomial(n,9)/512 for n in xrange(9,
31)] [From Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Mar 10
2009]
%Y A140354 Sequence in context: A125408 A140236 A004411 this_sequence A155673 A000833
A054329
%Y A140354 Adjacent sequences: A140351 A140352 A140353 this_sequence A140355 A140356
A140357
%K A140354 nonn
%O A140354 0,2
%A A140354 Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Jun 23 2008
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