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A374801
Irregular table T(n, k), n > 0, k = 1..A048691(n), read by rows; the n-th row lists the numbers m such that A003990(m) = n.
2
1, 2, 3, 5, 4, 6, 13, 7, 10, 12, 14, 25, 11, 15, 41, 8, 9, 16, 21, 23, 27, 31, 34, 61, 22, 28, 85, 29, 36, 38, 44, 59, 63, 113, 37, 45, 58, 64, 145, 17, 20, 46, 55, 57, 65, 96, 101, 181, 56, 66, 221, 18, 19, 40, 42, 67, 78, 80, 90, 94, 103, 109, 117, 142, 148, 265, 79, 91, 313
OFFSET
1,2
COMMENTS
A003990 corresponds to a square array, but we consider it here as a flat sequence (when its values are read according along its antidiagonals).
As a flat sequence this is a permutation of the positive integers with inverse A374802.
EXAMPLE
Triangle T(n, k) begins:
n n-th row
-- ----------------------------------------------------------------
1 1
2 2, 3, 5
3 4, 6, 13
4 7, 10, 12, 14, 25
5 11, 15, 41
6 8, 9, 16, 21, 23, 27, 31, 34, 61
7 22, 28, 85
8 29, 36, 38, 44, 59, 63, 113
9 37, 45, 58, 64, 145
10 17, 20, 46, 55, 57, 65, 96, 101, 181
11 56, 66, 221
12 18, 19, 40, 42, 67, 78, 80, 90, 94, 103, 109, 117, 142, 148, 265
13 79, 91, 313
14 30, 35, 92, 105, 107, 119, 197, 204, 365
PROG
(PARI) \\ See Links section.
CROSSREFS
Cf. A003990, A048691, A374802 (inverse).
Sequence in context: A121664 A352943 A143514 * A085180 A360209 A114750
KEYWORD
nonn,look,tabf
AUTHOR
Rémy Sigrist, Jul 20 2024
STATUS
approved