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A038291
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Triangle whose (i,j)-th entry is binomial(i,j)*9^(i-j)*1^j.
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3
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1, 9, 1, 81, 18, 1, 729, 243, 27, 1, 6561, 2916, 486, 36, 1, 59049, 32805, 7290, 810, 45, 1, 531441, 354294, 98415, 14580, 1215, 54, 1, 4782969, 3720087, 1240029, 229635, 25515, 1701, 63, 1, 43046721, 38263752, 14880348, 3306744, 459270
(list; table; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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COMMENTS
| T(i,j) is the number of i-permutations of 10 objects a,b,c,d,e,f,g,h,i,j with repetition allowed, containing j a's. - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Dec 21 2007
Reflected version of A013616. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Dec 19 2008]
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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.
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EXAMPLE
| 1
9, 1
81, 18, 1
729, 243, 27, 1
6561, 2916, 486, 36, 1
59049, 32805, 7290, 810, 45, 1
531441, 354294, 98415, 14580, 1215, 54, 1
4782969, 3720087, 1240029, 229635, 25515, 1701, 63, 1
43046721, 38263752, 14880348, 3306744, 459270, 40824, 2268, 72, 1
387420489, 387420489, 172186884, 44641044, 7440174, 826686, 61236,2916, 81, 1
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MAPLE
| for i from 0 to 9 do seq(binomial(i, j)*9^(i-j), j = 0 .. i) od; - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Dec 21 2007
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CROSSREFS
| Sequence in context: A050312 A107892 A050303 * A075504 A138342 A101678
Adjacent sequences: A038288 A038289 A038290 * A038292 A038293 A038294
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KEYWORD
| nonn,tabl,easy
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AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com).
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