OFFSET
1,3
LINKS
Peter Kagey, Table of n, a(n) for n = 1..9987 (first 1000 rows)
FORMULA
T(n,0) = n and T(n, A070939(n)) = 0.
EXAMPLE
For n = 26 and k = 2, T(26, 2) = 2 because 26 = 11010_2, and removing the first two bits leaves 010_2 = 2.
Table begins:
n\k| 0 1 2 3 4
---+-----------
1 | 1 0
2 | 2 0 0
3 | 3 1 0
4 | 4 0 0 0
5 | 5 1 1 0
6 | 6 2 0 0
7 | 7 3 1 0
8 | 8 0 0 0 0
9 | 9 1 1 1 0
MATHEMATICA
T[n_, k_] := BitAnd[n, 2^k-1]; Table[T[n, k], {n, 1, 20}, {k, BitLength[n], 0, -1}] // Flatten (* Amiram Eldar, Aug 09 2019 *)
PROG
(Ruby)
def t(n, k); n & (1 << n.bit_length - k) - 1 end
CROSSREFS
KEYWORD
nonn,tabf,base
AUTHOR
Peter Kagey, Aug 08 2019
STATUS
approved