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 A084135 a(n) = 10*a(n-1) - 15*a(n-2), a(0)=1, a(1)=5. 1
 1, 5, 35, 275, 2225, 18125, 147875, 1206875, 9850625, 80403125, 656271875, 5356671875, 43722640625, 356876328125, 2912923671875, 23776091796875, 194067062890625, 1584029251953125, 12929286576171875, 105532426982421875 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Binomial transform of A084134. LINKS Index entries for linear recurrences with constant coefficients, signature (10, -15). FORMULA a(n) = (5+sqrt(10))^n/2 + (5-sqrt(10))^n/2; g.f.: (1-5x)/(1-10x+15x^2); e.g.f.: exp(5x)cosh(sqrt(10)x). MATHEMATICA LinearRecurrence[{10, -15}, {1, 5}, 30] (* Harvey P. Dale, Oct 10 2012 *) PROG (PARI) a(n)=if(n<0, 0, polsym(x^2-10*x+15, n)[1+n]/2) CROSSREFS Sequence in context: A292839 A180900 A087630 * A229111 A138233 A322666 Adjacent sequences:  A084132 A084133 A084134 * A084136 A084137 A084138 KEYWORD easy,nonn AUTHOR Paul Barry, May 16 2003 STATUS approved

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Last modified April 19 08:15 EDT 2021. Contains 343110 sequences. (Running on oeis4.)