0,2

T(i,j) is the number of i-permutations of 5 objects a,b,c,d,e, with repetition allowed, containing j a's. - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Dec 21 2007

Triangle of coefficients in expansion of (4+x)^n - Nour-Eddine Fahssi (fahssin(AT)yahoo.fr), Apr 13 2008

B. N. Cyvin et al., Isomer enumeration of unbranched catacondensed polygonal systems with pentagons and heptagons, Match, No. 34 (Oct 1996), pp. 109-121.

Naiomi T. Cameron and Asamoah Nkwanta, On Some (Pseudo) Involutions in the Riordan Group, Journal of Integer Sequences, Vol. 8 (2005), Article 05.3.7.

G.f. for j-th column is (x^j)/(1-4*x)^(j+1); convolution triangle of A000302 (powers of 4).

Sum_{k, 0<=k<=n} T(n,k)*(-1)^k*A000108(k)= A001700(n). [From Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Nov 27 2009]

1

4, 1

16, 8, 1

64, 48, 12, 1

256, 256, 96, 16, 1

1024, 1280, 640, 160, 20, 1

4096, 6144, 3840, 1280, 240, 24, 1

16384, 28672, 21504, 8960, 2240, 336, 28, 1

65536, 131072, 114688, 57344, 17920, 3584, 448, 32, 1

for i from 0 to 8 do seq(binomial(i, j)*4^(i-j), j = 0 .. i) od; - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Dec 21 2007

Sequence in context: A094361 A067425 A138681 this_sequence A104855 A143496 A143697

Adjacent sequences: A038228 A038229 A038230 this_sequence A038232 A038233 A038234

nonn,tabl,easy,new

N. J. A. Sloane (njas(AT)research.att.com).