Complement of triangular numbers (A000217); also array T(n,k) = ((n+k)^2 + n-k)/2, n, k > 0, read by antidiagonals.

A014132

Complement of triangular numbers (A000217); also array T(n,k) = ((n+k)^2 + n-k)/2, n, k > 0, read by antidiagonals.

Terms

    a(0) =2a(1) =4a(2) =5a(3) =7a(4) =8a(5) =9a(6) =11a(7) =12a(8) =13a(9) =14a(10) =16a(11) =17a(12) =18a(13) =19a(14) =20a(15) =22a(16) =23a(17) =24a(18) =25a(19) =26a(20) =27a(21) =29a(22) =30a(23) =31a(24) =32a(25) =33a(26) =34a(27) =35a(28) =37a(29) =38

External references