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A023711 Numbers with exactly 2 1's in base 4 expansion. 1
5, 17, 20, 22, 23, 25, 29, 37, 53, 65, 68, 70, 71, 73, 77, 80, 82, 83, 88, 90, 91, 92, 94, 95, 97, 100, 102, 103, 105, 109, 113, 116, 118, 119, 121, 125, 133, 145, 148, 150, 151, 153, 157, 165, 181, 197, 209, 212, 214, 215, 217 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..51.

MATHEMATICA

Select[ Range[ 240 ], (Count[ IntegerDigits[ #, 4 ], 1 ]==2)& ]

CROSSREFS

Sequence in context: A252232 A162862 A043338 * A045119 A045095 A061940

Adjacent sequences:  A023708 A023709 A023710 * A023712 A023713 A023714

KEYWORD

nonn,base,easy

AUTHOR

Olivier Gérard

STATUS

approved

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Last modified January 21 13:55 EST 2020. Contains 331113 sequences. (Running on oeis4.)