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A023735
Numbers with exactly 2 3's in their base-5 expansion.
4
18, 43, 68, 78, 83, 88, 90, 91, 92, 94, 98, 118, 143, 168, 193, 203, 208, 213, 215, 216, 217, 219, 223, 243, 268, 293, 318, 328, 333, 338, 340, 341, 342, 344, 348, 368, 378, 383, 388, 390, 391, 392, 394, 398, 403, 408, 413, 415, 416, 417, 419, 423
OFFSET
1,1
LINKS
MAPLE
seq(`if`(numboccur(3, convert(n, base, 5))=2, n, NULL), n=0..450); # Nathaniel Johnston, Jun 27 2011
MATHEMATICA
Select[ Range[ 450 ], (Count[ IntegerDigits[ #, 5 ], 3 ]==2)& ]
Select[Range[500], DigitCount[#, 5, 3]==2&] (* Harvey P. Dale, Mar 24 2021 *)
CROSSREFS
Sequence in context: A252747 A067750 A043362 * A045300 A045189 A044095
KEYWORD
nonn,base,easy
STATUS
approved