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A295473
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a(0) = 0; for n>0, a(n) = 9*n!.
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1
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0, 9, 18, 54, 216, 1080, 6480, 45360, 362880, 3265920, 32659200, 359251200, 4311014400, 56043187200, 784604620800, 11769069312000, 188305108992000, 3201186852864000, 57621363351552000, 1094805903679488000, 21896118073589760000, 459818479545384960000
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OFFSET
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0,2
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LINKS
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FORMULA
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E.g.f.: 9*x/(1-x).
a(n) = n*a(n-1) = 9*A000142(n) for n>0.
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MATHEMATICA
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Join[{0}, 9 Range[25]!]
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PROG
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(Magma) [n eq 0 select 0 else 9*Factorial(n): n in [0..25]];
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CROSSREFS
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Cf. similar sequences listed in A298881.
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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