Search: id:A087405 Results 1-1 of 1 results found. %I A087405 %S A087405 2,2,22,98,502,2498,12502,62498,312502,1562498,7812502,39062498, %T A087405 195312502,976562498,4882812502,24414062498,122070312502,610351562498, %U A087405 3051757812502,15258789062498,76293945312502,381469726562498 %N A087405 First differences of A087404: a(n)=A087404(n)-A087404(n-1), a(0)=A087404(0). %F A087405 G.f.: ((1-x)(2-4x))/(1-4x-5x^2). For n>0: a(n)=4*5^(n-1)+2(-1)^n %t A087405 CoefficientList[Series[((1 - x)(2 - 4x))/(1 - 4x - 5x^2), {x, 0, 25}], x] %Y A087405 Sequence in context: A143807 A118454 A118326 this_sequence A001012 A040082 A014358 %Y A087405 Adjacent sequences: A087402 A087403 A087404 this_sequence A087406 A087407 A087408 %K A087405 easy,nonn %O A087405 0,1 %A A087405 Mario Catalani (mario.catalani(AT)unito.it), Sep 01 2003 Search completed in 0.001 seconds