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A023720 Numbers with exactly 3 3's in base 4 expansion. 1
63, 127, 191, 207, 223, 239, 243, 247, 251, 252, 253, 254, 319, 383, 447, 463, 479, 495, 499, 503, 507, 508, 509, 510, 575, 639, 703, 719, 735, 751, 755, 759, 763, 764, 765, 766, 783, 799, 815, 819, 823, 827, 828, 829, 830 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

MATHEMATICA

Select[ Range[ 864 ], (Count[ IntegerDigits[ #, 4 ], 3 ]==3)& ]

CROSSREFS

Sequence in context: A256813 A324488 A080947 * A031468 A045064 A043450

Adjacent sequences:  A023717 A023718 A023719 * A023721 A023722 A023723

KEYWORD

nonn,base,easy

AUTHOR

Olivier Gérard

STATUS

approved

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Last modified December 2 23:22 EST 2021. Contains 349445 sequences. (Running on oeis4.)