0,2

With a different offset, number of n-permutations of 7 objects:s,t,u,v,z,x, y with repetition allowed, containing exactly five (5) u's. Example: a(1)=36 because we have uuuuus, uuuusu, uuusuu, uusuuu, usuuuu, suuuuu, uuuuut, uuuutu, uuutuu, uutuuu, utuuuu, tuuuuu, uuuuuv, uuuuvu, uuuvuu, uuvuuu, uvuuuu, vuuuuu, uuuuuz, uuuuzu, uuuzuu, uuzuuu, uzuuuu, zuuuuu, uuuuux, uuuuxu, uuuxuu, uuxuuu, uxuuuu, xuuuuu, uuuuuy, uuuuyu, uuuyuu, uuyuuu, uyuuuu, yuuuuu. - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Jun 16 2008

a(n) = 6^n*binomial(n+5, 5); G.f. 1/(1-6*x)^6.

seq(binomial(n+5, 5)*6^n, n=0..17); - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Jun 16 2008

A001787, A036071.

Adjacent sequences: A036081 A036082 A036083 this_sequence A036085 A036086 A036087

Sequence in context: A004329 A089909 A049434 this_sequence A004338 A014772 A110206

easy,nonn

Wolfdieter Lang (wolfdieter.lang(AT)physik.uni-karlsruhe.de)