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A038232 Triangle whose (i,j)-th entry is binomial(i,j)*4^(i-j)*2^j. 0
1, 4, 2, 16, 16, 4, 64, 96, 48, 8, 256, 512, 384, 128, 16, 1024, 2560, 2560, 1280, 320, 32, 4096, 12288, 15360, 10240, 3840, 768, 64, 16384, 57344, 86016, 71680, 35840, 10752, 1792, 128, 65536, 262144, 458752, 458752, 286720, 114688 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..41.

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 - 4*x - 2*x*y). - Ilya Gutkovskiy, Apr 21 2017

CROSSREFS

Sequence in context: A316463 A167784 A053125 * A254632 A084623 A264195

Adjacent sequences:  A038229 A038230 A038231 * A038233 A038234 A038235

KEYWORD

nonn,tabl,easy

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified September 28 13:24 EDT 2020. Contains 337393 sequences. (Running on oeis4.)