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A038255 Triangle whose (i,j)-th entry is binomial(i,j)*6^(i-j). 9
1, 6, 1, 36, 12, 1, 216, 108, 18, 1, 1296, 864, 216, 24, 1, 7776, 6480, 2160, 360, 30, 1, 46656, 46656, 19440, 4320, 540, 36, 1, 279936, 326592, 163296, 45360, 7560, 756, 42, 1, 1679616, 2239488, 1306368, 435456, 90720, 12096, 1008 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

T(n,k) = A013613(n,n-k), 0 <= k <= n. - Reinhard Zumkeller, Nov 21 2013

LINKS

Reinhard Zumkeller, Rows n = 0..125 of triangle, flattened

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.

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

FORMULA

G.f.: 1/(1 - 6*x - x*y). - Ilya Gutkovskiy, Apr 21 2017

EXAMPLE

1

6, 1

36, 12, 1

216, 108, 18, 1

1296, 864, 216, 24, 1

7776, 6480, 2160, 360, 30, 1

46656, 46656, 19440, 4320, 540, 36, 1

279936, 326592, 163296, 45360, 7560, 756, 42, 1

1679616, 2239488, 1306368, 435456, 90720, 12096, 1008, 48, 1

MAPLE

for i from 0 to 8 do seq(binomial(i, j)*6^(i-j), j = 0 .. i) od; # Zerinvary Lajos, Dec 21 2007

PROG

(Haskell)

a038255 n k = a038255_tabl !! n !! k

a038255_row n = a038255_tabl !! n

a038255_tabl = map reverse a013613_tabl

-- Reinhard Zumkeller, Nov 21 2013

CROSSREFS

Cf. A038207.

Cf. A000420 (row sums), A013613 (mirrored), A110440, A007318, A000400.

Sequence in context: A241171 A051930 A147320 * A075501 A089504 A145927

Adjacent sequences:  A038252 A038253 A038254 * A038256 A038257 A038258

KEYWORD

nonn,tabl,easy

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified August 20 05:20 EDT 2018. Contains 313909 sequences. (Running on oeis4.)