# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a074608 Showing 1-1 of 1 %I A074608 #44 Oct 12 2015 09:39:53 %S A074608 2,10,58,370,2482,17050,118378,825730,5771362,40373290,282534298, %T A074608 1977503890,13841818642,96890604730,678227855818,4747575858850, %U A074608 33232973616322,232630643127370,1628413985330938,11398896347634610 %N A074608 a(n) = 3^n + 7^n. %H A074608 G. C. Greubel and Jon E. Schoenfield, Table of n, a(n) for n = 0..1000 (terms 0..160 from G. C. Greubel). %H A074608 Index entries for linear recurrences with constant coefficients, signature (10,-21). %F A074608 From _Mohammad K. Azarian_, Jan 11 2009: (Start) %F A074608 G.f.: 1/(1-3*x) + 1/(1-7*x). %F A074608 E.g.f.: exp(3*x) + exp(7*x). (End) %F A074608 a(n) = 10*a(n-1)-21*a(n-2) with a(0)=2, a(1)=10. - _Vincenzo Librandi_, Jul 21 2010 %F A074608 a(n) = 2 * A081336(n). - _Michel Marcus_, Oct 07 2015 %t A074608 Table[3^n + 7^n, {n, 0, 25}] %t A074608 RecurrenceTable[{a[0]== 2, a[1]== 10, a[n]== 10*a[n-1] - 21*a[n-2]}, a, {n,30}] (* _G. C. Greubel_, Aug 20 2015 *) %o A074608 (PARI) first(m)=vector(m,i,i--;3^i + 7^i) \\ _Anders Hellström_, Aug 20 2015 %o A074608 (PARI) Vec(1/(1-3*x) + 1/(1-7*x) + O(x^50)) \\ _Altug Alkan_, Oct 12 2015 %Y A074608 Cf. A000051, A034472, A052539, A034474, A062394, A034491, A062395, A062396, A007689, A063376, A063481, A074600 - A074624. %Y A074608 Cf. A081336. %K A074608 easy,nonn %O A074608 0,1 %A A074608 _Robert G. Wilson v_, Aug 25 2002 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE