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 A163141 a(n) = 5*a(n-2) for n > 2; a(1) = 4, a(2) = 5. 4
 4, 5, 20, 25, 100, 125, 500, 625, 2500, 3125, 12500, 15625, 62500, 78125, 312500, 390625, 1562500, 1953125, 7812500, 9765625, 39062500, 48828125, 195312500, 244140625, 976562500, 1220703125, 4882812500, 6103515625, 24414062500 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Apparently the same as A133632 without initial 1. Binomial transform is A163069, second binomial transform is A163070, third binomial transform is A163071, fourth binomial transform is A108404 without initial 1, fifth binomial transform is A163072. LINKS FORMULA a(n) = (5-3*(-1)^n)*5^(1/4*(2*n-1+(-1)^n))/2. G.f.: x*(4+5*x)/(1-5*x^2). PROG (MAGMA) [ n le 2 select n+3 else 5*Self(n-2): n in [1..29] ]; CROSSREFS Cf. A133632, A108404, A163069, A163070, A163071, A163072. Sequence in context: A080610 A047175 A133632 * A182584 A059182 A027958 Adjacent sequences:  A163138 A163139 A163140 * A163142 A163143 A163144 KEYWORD nonn AUTHOR Klaus Brockhaus, Jul 21 2009 STATUS approved

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