cp's OEIS Frontend

A085207 Array A(x,y): concatenation of binary expansions of x & y, listed antidiagonalwise as A(0,0), A(1,0), A(0,1), A(2,0), A(1,1), A(0,2), ... Zero is expanded as an empty string.

%I A085207 #9 May 18 2024 14:51:36
%S A085207 0,1,1,2,3,2,3,5,6,3,4,7,10,7,4,5,9,14,11,12,5,6,11,18,15,20,13,6,7,
%T A085207 13,22,19,28,21,14,7,8,15,26,23,36,29,22,15,8,9,17,30,27,44,37,30,23,
%U A085207 24,9,10,19,34,31,52,45,38,31,40,25,10,11,21,38,35,60,53,46,39,56,41,26,11
%N A085207 Array A(x,y): concatenation of binary expansions of x & y, listed antidiagonalwise as A(0,0), A(1,0), A(0,1), A(2,0), A(1,1), A(0,2), ... Zero is expanded as an empty string.
%e A085207 A(2,1) = 5 = '101' in binary, concatenation of 2's binary expansion '10' and 1's '1'. A(1,2) = 6 = '110' in binary, concatenation of '1' and '10'.
%o A085207 (MIT/GNU Scheme) (define (A085207bi x y) (+ (* (expt 2 (A029837 (1+ y))) x) y))
%o A085207 (define (A085207 n) (A085207bi (A025581 n) (A002262 n)))
%o A085207 (define (A085208 n) (A085207bi (A002262 n) (A025581 n)))
%Y A085207 Same array in binary: A085209. Transpose: A085208. Variant: A085211. Can be used to compute A085201.
%K A085207 nonn,tabl
%O A085207 0,4
%A A085207 _Antti Karttunen_, Jun 23 2003