Search: id:A138340 Results 1-1 of 1 results found. %I A138340 %S A138340 1,4,32,64,256,2048,4096,16384,131072,262144,1048576,8388608,16777216, %T A138340 67108864,536870912,1073741824,4294967296,34359738368,68719476736, %U A138340 274877906944,2199023255552,4398046511104,17592186044416 %V A138340 1,-4,-32,-64,256,2048,4096,-16384,-131072,-262144,1048576,8388608,16777216, -67108864, %W A138340 -536870912,-1073741824,4294967296,34359738368,68719476736,-274877906944, %X A138340 -2199023255552,-4398046511104,17592186044416 %N A138340 Expansion of (1-8x)/(1-4x+16x^2). %C A138340 abs(a(n))=2^A047267(n). %F A138340 a(n):=2*4^n(cos(pi*(n+1)/3)-sqrt(3)*sin(pi*(n+1))/3); %F A138340 a(n)=4^n*Sum_{k, 0<=k<=n} A121314(n,k)*(-1)^k*3^(n-k). [From Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Nov 01 2008] %F A138340 a(n)=A128018(n)*2^n. [From Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Nov 14 2008] %Y A138340 Sequence in context: A114076 A078092 A076137 this_sequence A113250 A012036 A153794 %Y A138340 Adjacent sequences: A138337 A138338 A138339 this_sequence A138341 A138342 A138343 %K A138340 easy,sign %O A138340 0,2 %A A138340 Paul Barry (pbarry(AT)wit.ie), Mar 15 2008 Search completed in 0.001 seconds