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A224139
Double 1's in binary representations of 2*n-1, converting to decimal and dividing by maximal possible power of 3.
1
1, 5, 1, 7, 17, 37, 41, 85, 11, 23, 73, 149, 1, 55, 169, 341, 65, 133, 137, 277, 145, 293, 11, 199, 161, 325, 329, 661, 337, 677, 227, 455, 43, 29, 265, 533, 91, 61, 553, 1109, 289, 581, 65, 391, 593, 1189, 1193, 2389, 107, 215, 649, 1301, 73, 439, 1321, 2645
OFFSET
1,2
LINKS
EXAMPLE
Let n=6, 2*n-1=11 which in binary 1011. Number with double 1's is 1101111 which in decimal 111. Thus a(6)=111/3=37.
MATHEMATICA
Map[#/3^IntegerExponent[#, 3]&[FromDigits[Flatten[IntegerDigits[2#-1, 2]/.{1->{1, 1}}], 2]]&, Range[100]] (* Peter J. C. Moses, Mar 31 2013 *)
CROSSREFS
Sequence in context: A332459 A051854 A006569 * A320905 A193860 A211849
KEYWORD
nonn,base
AUTHOR
Vladimir Shevelev, Mar 31 2013
STATUS
approved