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A221129
Numbers of form k*2^n + n where 1 <= k < 2^n and n > 0.
2
3, 6, 10, 11, 14, 19, 20, 27, 35, 36, 37, 43, 51, 52, 59, 68, 69, 70, 84, 100, 101, 116, 132, 133, 134, 135, 148, 164, 165, 180, 196, 197, 198, 212, 228, 229, 244, 261, 262, 263, 264, 293, 325, 326, 357, 389, 390, 391, 421, 453, 454, 485, 517, 518, 519, 520, 521
OFFSET
1,1
COMMENTS
Subsequence of primes: 3, 11, 19, 37, 43, 59, 101, 197, 229, 263, ...
LINKS
EXAMPLE
a(6) = 19 = 2 *2^3 + 3.
MAPLE
N:= 1000: # to get all terms <= N
sort([seq(seq(k*2^n+n, k=1..min(2^n-1, (N-n)/2^n)), n=1..ilog2(N))]); # Robert Israel, Jan 21 2019
MATHEMATICA
seqUpTo[n_] := Select[Union@Flatten@Table[k*2^h + h, {h, Floor@Log[2, n]}, {k, Min[2^h - 1, Floor[n/2^h]]}], # <= n &]; seqUpTo[521] (* Giovanni Resta, Jan 08 2013 *)
CROSSREFS
Sequence in context: A241858 A231668 A123053 * A138289 A219638 A105359
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Jan 02 2013
STATUS
approved