Search: id:A115512 Results 1-1 of 1 results found. %I A115512 %S A115512 1,1,1,0,0,1,0,0,0,1,0,1,0,0,1,0,0,0,0,0,1,0,0,0,0,0,0,1,0,0,1,0,0,0,0, %T A115512 1,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,1,0,0,0,1,0,0,0,0,0,0,1,0,0,0,0, %U A115512 0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,1,0,0,0,0,0,0,0,0,1 %N A115512 Number triangle (1,x)+(x,x^3) expressed in terms of Riordan arrays. %C A115512 Row sums are periodic {1,2,1}. Diagonal sums are periodic {1,1,1,0}. Inverse is A115513. %F A115512 Column k has g.f. x^k+x^(3k+1); Number triangle T(n, k)=if(n=k, 1, 0) OR if(n=3k+1, 1, 0). %e A115512 Triangle begins %e A115512 1, %e A115512 1, 1, %e A115512 0, 0, 1, %e A115512 0, 0, 0, 1, %e A115512 0, 1, 0, 0, 1, %e A115512 0, 0, 0, 0, 0, 1, %e A115512 0, 0, 0, 0, 0, 0, 1, %e A115512 0, 0, 1, 0, 0, 0, 0, 1, %e A115512 0, 0, 0, 0, 0, 0, 0, 0, 1, %e A115512 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, %e A115512 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, %e A115512 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, %e A115512 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, %e A115512 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, %e A115512 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, %e A115512 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, %e A115512 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, %e A115512 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, %e A115512 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, %e A115512 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, %e A115512 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 %Y A115512 Sequence in context: A096606 A128190 A128189 this_sequence A115513 A133080 A010815 %Y A115512 Adjacent sequences: A115509 A115510 A115511 this_sequence A115513 A115514 A115515 %K A115512 easy,nonn,tabl %O A115512 0,1 %A A115512 Paul Barry (pbarry(AT)wit.ie), Jan 23 2006 Search completed in 0.001 seconds