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A038299 Triangle whose (i,j)-th entry is binomial(i,j)*9^(i-j)*9^j. 2
1, 9, 9, 81, 162, 81, 729, 2187, 2187, 729, 6561, 26244, 39366, 26244, 6561, 59049, 295245, 590490, 590490, 295245, 59049, 531441, 3188646, 7971615, 10628820, 7971615, 3188646, 531441, 4782969, 33480783, 100442349, 167403915 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,2

REFERENCES

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

LINKS

Table of n, a(n) for n=0..31.

FORMULA

Row sums: sum_{j=0..i} T(i,j) = A001027(i). [From R. J. Mathar, Mar 30 2009]

CROSSREFS

Sequence in context: A152018 A223744 A112296 * A323210 A215272 A165427

Adjacent sequences:  A038296 A038297 A038298 * A038300 A038301 A038302

KEYWORD

nonn,tabl,easy

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified October 23 21:57 EDT 2019. Contains 328373 sequences. (Running on oeis4.)