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Lexicographically earliest sequence of distinct nonnegative integers such that the product of two terms, not necessarily distinct, can be computed without carry in base 3.
2

%I #11 Jun 21 2021 03:04:59

%S 0,1,3,4,9,10,12,27,28,30,31,36,81,82,84,85,90,93,108,243,244,246,247,

%T 252,253,255,270,279,324,729,730,732,733,738,739,741,756,759,765,810,

%U 837,972,2187,2188,2190,2191,2196,2197,2199,2214,2215,2217,2218,2223

%N Lexicographically earliest sequence of distinct nonnegative integers such that the product of two terms, not necessarily distinct, can be computed without carry in base 3.

%C All terms belong to A005836.

%C If m is a term, then 3*m is also a term (in particular, all powers of 3 appear in the sequence).

%C The representation of the 1's in the ternary expansion of consecutive terms has interesting features (see illustration in Links section).

%H Rémy Sigrist, <a href="/A345359/b345359.txt">Table of n, a(n) for n = 1..2500</a>

%H Rémy Sigrist, <a href="/A345359/a345359.png">Binary plot of (n, A289831(a(n))) for n = 1..255</a> (representation of the 1's in the ternary expansion of the first 255 terms)

%H Rémy Sigrist, <a href="/A345359/a345359.gp.txt">PARI program for A345359</a>

%F A053735(a(m) * a(n)) = A053735(a(m)) * A053735(a(n)).

%o (PARI) See Links section.

%Y Cf. A005836, A053735, A131577 (binary analog), A289831, A345358 (decimal analog).

%K nonn,base

%O 1,3

%A _Rémy Sigrist_, Jun 16 2021