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A371265
Irregular triangle T(n, k), n >= 0, read by rows; the n-th row lists the numbers m such that A371263(m) = n.
4
0, 1, 2, 3, 4, 5, 9, 6, 7, 8, 10, 11, 12, 13, 14, 27, 15, 16, 26, 28, 17, 19, 20, 21, 24, 25, 29, 30, 18, 22, 23, 31, 32, 36, 33, 34, 35, 37, 38, 39, 40, 41, 81, 42, 43, 80, 82, 44, 46, 47, 48, 78, 79, 83, 84, 45, 49, 77, 85, 50, 58, 59, 63, 72, 76, 86, 90
OFFSET
0,3
COMMENTS
Row 0 has 1 term; for n > 0, row n has A225081(n-1) terms.
As a flat sequence, this is a permutation of the nonnegative integers, with inverse A371266.
EXAMPLE
Triangle T(n, k) begins:
n n-th row
-- ------------------------------
0 0
1 1
2 2, 3
3 4
4 5, 9
5 6, 7, 8, 10
6 11, 12
7 13
8 14, 27
9 15, 16, 26, 28
10 17, 19, 20, 21, 24, 25, 29, 30
11 18, 22, 23, 31
12 32, 36
13 33, 34, 35, 37
14 38, 39
15 40
.
Triangle T(n, k) begins, in balanced ternary, with row indexes in binary:
bin(n) n-th row in balanced ternary
------ ----------------------------------------------
0 0
1 1
10 1T, 10
11 11
100 1TT, 100
101 1T0, 1T1, 10T, 101
110 11T, 110
111 111
1000 1TTT, 1000
1001 1TT0, 1TT1, 100T, 1001
1010 1T0T, 1T01, 1T1T, 1T10, 10T0, 10T1, 101T, 1010
1011 1T00, 1T11, 10TT, 1011
1100 11TT, 1100
1101 11T0, 11T1, 110T, 1101
1110 111T, 1110
1111 1111
PROG
(PARI) \\ See Links section.
CROSSREFS
See A371257 for a similar sequence.
Cf. A225081, A371266 (inverse).
Sequence in context: A289081 A105950 A227778 * A166276 A374950 A101544
KEYWORD
nonn,base,tabf
AUTHOR
Rémy Sigrist, Mar 16 2024
STATUS
approved