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A201651
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.
2
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, 18, 13, 24, 19, 22, 25, 28, 8, 9, 10, 11, 12, 13, 14, 15, 32, 9, 12, 11, 14, 13, 24, 15, 26, 33, 36, 10, 11, 32, 33, 14, 15, 36, 37, 34, 35, 40, 11, 14, 33, 36
OFFSET
0,3
LINKS
EXAMPLE
Triangle begins
0;
1, 4;
2, 3, 8;
3, 6, 9, 12;
4, 5, 6, 7, 16;
PROG
(Haskell)
import Data.Bits (xor, (.&.), shift)
a201651 :: Integer -> Integer -> Integer
a201651 n 0 = n
a201651 n k = a054240 (n `xor` k) (shift (n .&. k) 2)
a201651_row n = map (a054240 n) [0..n]
a201651_tabl = map a201651_row [0..]
CROSSREFS
Cf. A054240 (square array read by antidiagonals).
Sequence in context: A143054 A195953 A016512 * A357463 A349119 A026246
KEYWORD
nonn,tabl
AUTHOR
Reinhard Zumkeller, Dec 03 2011
STATUS
approved