Search: id:A081768 Results 1-1 of 1 results found. %I A081768 %S A081768 1,2,3,3,5,5,3,7,7,5,7,5,7,11,9,3,5,13,9,13,7,3,11,9,7,9,7,11,11,9,3,9, %T A081768 23,13,19,9,3,7,11,7,11,9,9,9,7,7,5,19,13,23,15,7,17,13,9,7,5,5,7,11,11, %U A081768 11,19,11,15,9,11,21,19,11,9,9,9,13,11,5,13,21,9,11,15,7,13,9,7,11,7,15 %N A081768 Number of k, 1<=k<=n, such that C(n,k) divides C(2n,2k). %C A081768 Is a(n) odd for n>2 ? All odd numbers occur? Does equation a(x)=2m+1 have infinitely many solutions for any m>=1? %Y A081768 Sequence in context: A158745 A103310 A046146 this_sequence A072923 A131922 A113730 %Y A081768 Adjacent sequences: A081765 A081766 A081767 this_sequence A081769 A081770 A081771 %K A081768 easy,nonn %O A081768 1,2 %A A081768 Benoit Cloitre (benoit7848c(AT)orange.fr), Apr 09 2003 Search completed in 0.001 seconds