A201651 - OEIS

%I #12 Jul 13 2013 12:04:19

%S 0,1,4,2,3,8,3,6,9,12,4,5,6,7,16,5,16,7,18,17,20,6,7,12,13,18,19,24,7,

%T 18,13,24,19,22,25,28,8,9,10,11,12,13,14,15,32,9,12,11,14,13,24,15,26,

%U 33,36,10,11,32,33,14,15,36,37,34,35,40,11,14,33,36

%N Bit-interleaved number addition table (cf. A054240) as triangle read by rows: T(n,k) = n and k added in binary representation, where carries shift 2 instead of 1, 0 <= k <= n.

%H Reinhard Zumkeller, <a href="/A201651/b201651.txt">Table of n, a(n) for n = 0..8000</a>

%e Triangle begins

%e 0;

%e 1, 4;

%e 2, 3, 8;

%e 3, 6, 9, 12;

%e 4, 5, 6, 7, 16;

%o (Haskell)

%o import Data.Bits (xor, (.&.), shift)

%o a201651 :: Integer -> Integer -> Integer

%o a201651 n 0 = n

%o a201651 n k = a054240 (n `xor` k) (shift (n .&. k) 2)

%o a201651_row n = map (a054240 n) [0..n]

%o a201651_tabl = map a201651_row [0..]

%Y Cf. A054240 (square array read by antidiagonals).

%K nonn,tabl

%O 0,3

%A _Reinhard Zumkeller_, Dec 03 2011