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A380123
Irregular table T(n, k), n >= 0, k = 1..A380122(n), read by rows; the n-th row lists the integers m (possibly negative) such that the nonzero digits in the nonadjacent form for m appear in the nonadjacent form for n.
2
0, 0, 1, 0, 2, -1, 0, 3, 4, 0, 4, 0, 1, 4, 5, -2, 0, 6, 8, -1, 0, 7, 8, 0, 8, 0, 1, 8, 9, 0, 2, 8, 10, -5, -4, -1, 0, 11, 12, 15, 16, -4, 0, 12, 16, -4, -3, 0, 1, 12, 13, 16, 17, -2, 0, 14, 16, -1, 0, 15, 16, 0, 16, 0, 1, 16, 17, 0, 2, 16, 18, -1, 0, 3, 4, 15, 16, 19, 20
OFFSET
0,5
LINKS
Rémy Sigrist, Table of n, a(n) for n = 0..6724 (rows for n = 0..2^9 flattened)
Joerg Arndt, Matters Computational (The Fxtbook), pages 61-62.
FORMULA
T(n, 1) = A184616(n).
T(n, A380122(n)) = n.
EXAMPLE
Irregular table T(n, k) begins:
n n-th row
-- -----------------------------
0 0
1 0, 1
2 0, 2
3 -1, 0, 3, 4
4 0, 4
5 0, 1, 4, 5
6 -2, 0, 6, 8
7 -1, 0, 7, 8
8 0, 8
9 0, 1, 8, 9
10 0, 2, 8, 10
11 -5, -4, -1, 0, 11, 12, 15, 16
12 -4, 0, 12, 16
13 -4, -3, 0, 1, 12, 13, 16, 17
14 -2, 0, 14, 16
15 -1, 0, 15, 16
16 0, 16
.
Irregular table T(n, k) begins in nonadjacent form:
n n-th row
----- ------------------------------------------
0 0
1 0, 1
10 0, 10
10T T, 0, 10T, 100
100 0, 100
101 0, 1, 100, 101
10T0 T0, 0, 10T0, 1000
100T T, 0, 100T, 1000
1000 0, 1000
1001 0, 1, 1000, 1001
1010 0, 10, 1000, 1010
10T0T T0T, T00, T, 0, 10T0T, 10T00, 1000T, 10000
10T00 T00, 0, 10T00, 10000
PROG
(PARI) row(n) = { my (r = [0], d, b = 1); while (n, if (n % 2, n -= d = 2 - (n%4); r = concat(r, [v + d*b | v <- r]); ); n /= 2; b *= 2; ); vecsort(r); }
CROSSREFS
See A295989 for a similar sequence.
Sequence in context: A049242 A108887 A337804 * A357368 A193401 A220399
KEYWORD
sign,base,tabf,new
AUTHOR
Rémy Sigrist, Jan 12 2025
STATUS
approved