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A143116
a(n) = the smallest positive multiple of n that has exactly n (nonleading) 0's in its binary representation.
2
2, 4, 18, 16, 65, 132, 518, 256, 1026, 2050, 4224, 8196, 16640, 65548, 262155, 65536, 262208, 524304, 1050624, 2097160, 8388618, 8388864, 33554562, 33554448, 67174400, 134218240, 268435458, 1073741844, 1073807360, 8589934620
OFFSET
1,1
LINKS
EXAMPLE
For n = 3, checking: 3*1=3 (11 in binary, zero 0's). 3*2=6 (110 in binary, one 0). 3*3=9 (1001 in binary, two 0's). 3*4=12 (1100 in binary, two 0's). 3*5=15 (1111 in binary, zero 0's). 3*6=18 (10010 in binary, three 0's). So a(3) = 18.
CROSSREFS
Cf. A143115.
Sequence in context: A275725 A242528 A137933 * A304856 A115987 A076692
KEYWORD
base,nonn
AUTHOR
Leroy Quet, Jul 25 2008
EXTENSIONS
a(6) to a(27) from Owen Whitby, Oct 22 2008. For n=28,29,30 if a(n) exists it is greater than 20000000n.
a(28)-a(30) from Ray Chandler, Nov 11 2008
STATUS
approved