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A067576
Array T(i,j) read by downward antidiagonals, where T(i,j) is the j-th term whose binary expansion has i 1's.
9
1, 2, 3, 4, 5, 7, 8, 6, 11, 15, 16, 9, 13, 23, 31, 32, 10, 14, 27, 47, 63, 64, 12, 19, 29, 55, 95, 127, 128, 17, 21, 30, 59, 111, 191, 255, 256, 18, 22, 39, 61, 119, 223, 383, 511, 512, 20, 25, 43, 62, 123, 239, 447, 767, 1023, 1024, 24, 26, 45, 79, 125, 247, 479, 895, 1535, 2047
OFFSET
1,2
COMMENTS
This is a permutation of the positive integers; the inverse permutation is A356419. - Jianing Song, Aug 06 2022
EXAMPLE
Array begins:
j=1 j=2 j=3 j=4 j=5 j=6
i=1: 1, 2, 4, 8, 16, 32, ...
i=2: 3, 5, 6, 9, 10, 12, ...
i=3: 7, 11, 13, 14, 19, 21, ...
i=4: 15, 23, 27, 29, 30, 39, ...
i=5: 31, 47, 55, 59, 61, 62, ...
i=6: 63, 95, 111, 119, 123, 125, ...
MATHEMATICA
a = {}; Do[ a = Append[a, Last[ Take[ Select[ Range[2^13], Count[ IntegerDigits[ #, 2], 1] == j & ], i - j]]], {i, 2, 12}, {j, 1, i - 1} ]; a
CROSSREFS
T(n,n) gives A036563(n+1).
The antidiagonals are read in the opposite direction from those in A066884.
Antidiagonal sums give A361074.
Sequence in context: A194068 A194062 A085177 * A364772 A107900 A112922
KEYWORD
base,easy,nonn,tabl
AUTHOR
Robert G. Wilson v, Jan 30 2002
STATUS
approved