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A067403
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Third column of triangle A067402.
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5
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1, 5, 45, 405, 3645, 32805, 295245, 2657205, 23914845, 215233605, 1937102445, 17433922005, 156905298045, 1412147682405, 12709329141645, 114383962274805, 1029455660473245, 9265100944259205, 83385908498332845
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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FORMULA
| a(n)= A067402(n+2, 2). a(n)= 5*9^(n-1), n>=1, a(0)=1.
G.f.: (1-4*x)/(1-9*x).
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MATHEMATICA
| Join[{1}, NestList[9#&, 5, 30]] (* or *) CoefficientList[Series[ (1-4x)/ (1-9x), {x, 0, 30}], x] (* From Harvey P. Dale, Apr 26 2011 *)
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CROSSREFS
| Cf. A002001 (second column), A067404 (fourth column), A001019 (powers of 9).
Sequence in context: A125836 A001260 A088505 * A173292 A173558 A022022
Adjacent sequences: A067400 A067401 A067402 * A067404 A067405 A067406
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KEYWORD
| nonn,easy
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AUTHOR
| Wolfdieter Lang (wolfdieter.lang(AT)physik.uni-karlsruhe.de), Jan 25 2002
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