# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a164045 Showing 1-1 of 1 %I A164045 #17 Sep 29 2023 10:17:24 %S A164045 1,4,18,87,431,2150,10744,53713,268557,1342776,6713870,33569339, %T A164045 167846683,839233402,4196166996,20980834965,104904174809,524520874028, %U A164045 2622604370122,13113021850591,65565109252935,327825546264654 %N A164045 a(n+1) = 5*a(n) - n. %H A164045 G. C. Greubel, Table of n, a(n) for n = 0..1000 %H A164045 Index entries for linear recurrences with constant coefficients, signature (7, -11, 5). %F A164045 a(0)=1; a(n+1) = 5*a(n) - n. %F A164045 a(n) = (11*5^n + 4*n + 5)/16. %F A164045 From _R. J. Mathar_, Aug 09 2009: (Start) %F A164045 a(n) = 7*a(n-1) - 11*a(n-2) + 5*a(n-3). %F A164045 G.f.: (1-3*x+x^2)/((1-5*x)*(1-x)^2). (End) %F A164045 E.g.f.: (1/16)*(11*exp(5*x) + (4*x + 5)*exp(x)). - _G. C. Greubel_, Sep 08 2017 %t A164045 Table[(11*5^n + 4*n + 5)/16, {n,0,50}] (* _G. C. Greubel_, Sep 08 2017 *) %t A164045 LinearRecurrence[{7,-11,5},{1,4,18},30] (* or *) nxt[{n_,a_}]:={n+1,5a-n-1}; NestList[nxt,{0,1},30][[;;,2]] (* _Harvey P. Dale_, Sep 29 2023 *) %o A164045 (PARI) a(n) = (11*5^n + 4*n + 5)/16 \\ _Michel Marcus_, Jul 18 2013 %K A164045 nonn %O A164045 0,2 %A A164045 _Rolf Pleisch_, Aug 08 2009 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE