Search: id:A010673 Results 1-1 of 1 results found. %I A010673 %S A010673 0,2,0,2,0,2,0,2,0,2,0,2,0,2,0,2,0,2,0,2,0,2,0,2,0,2,0,2,0,2,0,2,0,2,0, %T A010673 2,0,2,0,2,0,2,0,2,0,2,0,2,0,2,0,2,0,2,0,2,0,2,0,2,0,2,0,2,0,2,0,2,0,2, %U A010673 0,2,0,2,0,2,0,2,0,2,0,2,0,2,0,2,0,2,0,2,0,2,0,2,0,2,0,2,0,2,0,2,0,2,0 %N A010673 Period 2. %C A010673 Euler number (or Euler characteristic) of (n+1)-sphere. - Franz Vrabec (franz.vrabec(AT)planetuniqa.at), Sep 07 2007 %C A010673 Submitted A153735=-1,0,0,2,4,10,20,. a(n+1)=A153735(n+1)-2*A153735(n). [From Paul Curtz (bpcrtz(AT)free.fr), Jan 01 2009] %D A010673 R. Carter, G. Segal, I. Macdonald, Lectures on Lie Groups and Lie Algebras, London Mathematical Society Student Texts 32, Cambridge University Press, 1995; see p. 68. %F A010673 1-(-1^n). %F A010673 a(n)=2*(n mod 2) - Paolo P. Lava (ppl(AT)spl.at), Oct 20 2006 %Y A010673 Sequence in context: A096972 A101227 A021499 this_sequence A084099 A036665 A053472 %Y A010673 Adjacent sequences: A010670 A010671 A010672 this_sequence A010674 A010675 A010676 %K A010673 nonn,easy %O A010673 0,2 %A A010673 N. J. A. Sloane (njas(AT)research.att.com). Search completed in 0.001 seconds