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A217313
Numbers for which there exist a base in which n contains more 1's than in binary.
1
4, 8, 16, 32, 40, 64, 112, 128, 129, 130, 148, 256, 257, 258, 259, 260, 274, 280, 292, 328, 336, 337, 352, 364, 388, 392, 400, 448, 512, 580, 608, 656, 768, 769, 770, 772, 776, 784, 832, 850, 1024, 1025, 1026, 1030, 1032, 1036, 1040, 1042, 1048, 1056, 1057, 1058, 1060, 1064, 1065
OFFSET
1,1
COMMENTS
Numbers n for which A062843(n) != A000120(n).
Every number of the form 2^m with m > 1 is included in the list.
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
EXAMPLE
40 is 111 (3 ones) in base 3 and 101000 (2 ones) in base 2, therefore it is in the sequence.
MATHEMATICA
Select[Table[n, {n, 1, 1000}], Max[Table[Count[IntegerDigits[#, b], 1], {b, 2, # + 1}]] != Count[IntegerDigits[#, 2], 1] &]
PROG
(PARI) ones(n, b)=my(s); while(n, if(n%b==1, s++); n\=b); s
is(n)=if(n<4, return(0)); my(m=hammingweight(n), b=2); while(b++^(m-1)<n, if(ones(n, b)>m, return(1))); 0 \\ Charles R Greathouse IV, Mar 19 2013
CROSSREFS
Sequence in context: A283052 A088259 A123857 * A101434 A293780 A048168
KEYWORD
nonn,base
AUTHOR
Benedikt Otten, Mar 17 2013
STATUS
approved