login
This site is supported by donations to The OEIS Foundation.
Logo

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A038299 Triangle whose (i,j)-th entry is binomial(i,j)*9^(i-j)*9^j. 1
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; 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.

FORMULA

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

CROSSREFS

Sequence in context: A165830 A152018 A112296 * A165427 A050683 A092548

Adjacent sequences:  A038296 A038297 A038298 * A038300 A038301 A038302

KEYWORD

nonn,tabl,easy

AUTHOR

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

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified February 15 08:20 EST 2012. Contains 205729 sequences.