This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A274636 #9 Jul 08 2016 19:44:54 %S A274636 4,4,6,6,6,6,6,9,6,10,10,9,9,10,10,10,15,9,15,10,18,18,15,15,15,15,18, %T A274636 18,18,27,15,25,15,27,18,34,34,27,27,25,25,27,27,34,34,34,51,27,45,25, %U A274636 45,27,51,34,66,66,51,51,45,45,45,45,51,51,66,66,66,99,51,85,45,81,45,85,51,99,66,130 %N A274636 Square array read by antidiagonals: T(m,n) (m>=0, n>=0) = (2^floor(m/2)+1)*(2^ceiling(n/2)+1). %e A274636 The array begins: %e A274636 4, 6, 6, 10, 10, 18, 18, 34, 34, 66, 66, 130, 130, ... %e A274636 4, 6, 6, 10, 10, 18, 18, 34, 34, 66, 66, 130, 130, ... %e A274636 6, 9, 9, 15, 15, 27, 27, 51, 51, 99, 99, 195, 195, ... %e A274636 6, 9, 9, 15, 15, 27, 27, 51, 51, 99, 99, 195, 195, ... %e A274636 10, 15, 15, 25, 25, 45, 45, 85, 85, 165, 165, 325, 325, ... %e A274636 10, 15, 15, 25, 25, 45, 45, 85, 85, 165, 165, 325, 325, ... %e A274636 18, 27, 27, 45, 45, 81, 81, 153, 153, 297, 297, 585, 585, ... %e A274636 ... %Y A274636 The main diagonal is conjectured to be A183978. Cf. A274635, A274637. %K A274636 nonn,tabl %O A274636 0,1 %A A274636 _N. J. A. Sloane_, Jul 08 2016