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A368316
Lexicographically earliest sequence of distinct nonnegative integers such that for any n >= 0, a(n) and Sum_{k = 0..n-1} a(k) can be added without carries in balanced ternary.
1
0, 1, 2, 5, 3, 15, 4, 6, 41, 9, 18, 10, 125, 12, 16, 8, 45, 13, 14, 369, 27, 54, 28, 11, 7, 126, 17, 55, 26, 1107, 30, 51, 31, 131, 36, 46, 29, 375, 37, 44, 39, 123, 40, 42, 35, 3285, 57, 24, 135, 81, 405, 82, 38, 19, 132, 53, 1134, 84, 25, 134, 85, 23, 378
OFFSET
0,3
COMMENTS
Two integers can be added without carries in balanced ternary if they have no equal nonzero digit at the same position.
If we restrict ourselves to positive integers and allow duplicates, then we obtain A236313.
This sequence can be seen as a variant of A278742; however, the present sequence is not strictly increasing.
Will every nonnegative integer appear in the sequence?
EXAMPLE
The first terms, alongside the balanced ternary expansions of a(n) and b(n) = Sum_{k = 0..n-1} a(k), are:
n | 0 1 2 3 4 5 6 7 8 9 10
a(n) | 0 1 2 5 3 15 4 6 41 9 18
bter(b(n)) | 0 0 1 10 10T 11T 100T 1010 1100 100TT 101TT
bter(a(n)) | 0 1 1T 1TT 10 1TT0 11 1T0 1TTTT 100 1T00
PROG
(PARI) See Links section.
CROSSREFS
Sequence in context: A285742 A245612 A243066 * A181921 A282575 A002565
KEYWORD
nonn,base
AUTHOR
Rémy Sigrist, Dec 21 2023
STATUS
approved