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A045100
Numbers whose base-4 representation contains exactly three 1's and no 2's.
0
21, 69, 81, 84, 87, 93, 117, 213, 261, 273, 276, 279, 285, 309, 321, 324, 327, 333, 336, 339, 348, 351, 369, 372, 375, 381, 453, 465, 468, 471, 477, 501, 789, 837, 849, 852, 855, 861, 885, 981, 1029, 1041, 1044, 1047, 1053, 1077
OFFSET
1,1
MATHEMATICA
Select[Range[1200], DigitCount[#, 4, 1]==3&&DigitCount[#, 4, 2]==0&] (* Harvey P. Dale, Dec 30 2022 *)
CROSSREFS
Cf. A007090.
Sequence in context: A043339 A023712 A045124 * A038471 A224072 A020150
KEYWORD
nonn,base
STATUS
approved