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A044993 Numbers n with property that in base 3 representation the numbers of 0's and 2's are 0 and 4, respectively. 1
80, 161, 215, 233, 239, 241, 404, 458, 476, 482, 484, 620, 638, 644, 646, 692, 698, 700, 716, 718, 724, 1133, 1187, 1205, 1211, 1213, 1349, 1367, 1373, 1375, 1421, 1427, 1429, 1445, 1447, 1453, 1835, 1853, 1859, 1861, 1907 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(A000389(k)) = (161*3^(k-5)-1)/2 for k >= 5. - Robert Israel, Sep 21 2020

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

MAPLE

f:= proc(d) local C, c;

   C:= combinat:-choose(d, 4);

   c:=(3^(d)-1)/2;

   op(sort([seq(c+add(3^(i-1), i=t), t=C)]))

end proc:

seq(f(d), d=4..8); # Robert Israel, Sep 21 2020

CROSSREFS

Cf. A000389.

Sequence in context: A043332 A023702 A031460 * A043486 A031496 A044331

Adjacent sequences:  A044990 A044991 A044992 * A044994 A044995 A044996

KEYWORD

nonn,base

AUTHOR

Clark Kimberling

STATUS

approved

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Last modified June 12 10:58 EDT 2021. Contains 344947 sequences. (Running on oeis4.)