A038299 Triangle whose (i,j)-th entry is binomial(i,j)*9^(i-j)*9^j.

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

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn
• tabl
• easy

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.

Formula

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