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A045090
Numbers whose base-4 representation contains exactly one 1 and no 2's.
0
1, 4, 7, 13, 16, 19, 28, 31, 49, 52, 55, 61, 64, 67, 76, 79, 112, 115, 124, 127, 193, 196, 199, 205, 208, 211, 220, 223, 241, 244, 247, 253, 256, 259, 268, 271, 304, 307, 316, 319, 448, 451, 460, 463, 496, 499, 508, 511, 769, 772
OFFSET
1,2
MATHEMATICA
Select[Range[800], DigitCount[#, 4, 1]==1&&DigitCount[#, 4, 2]==0&] (* Harvey P. Dale, Jan 11 2013 *)
CROSSREFS
Cf. A007090.
Sequence in context: A202822 A374135 A137827 * A213382 A258867 A074273
KEYWORD
nonn,base
STATUS
approved