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A253258 Square array read by antidiagonals, j>=1, k>=1: T(j,k) is the j-th number n such that the symmetric representation of sigma(n) has at least a part with maximum width k. 2
1, 2, 6, 3, 12, 60, 4, 15, 72, 120, 5, 18, 84, 180, 360, 7, 20, 90, 240, 420, 840, 8, 24, 126, 252, 720, 1080, 3360, 9, 28, 140, 336, 1008, 1260, 3600, 2520, 10, 30, 144, 378, 1200, 1440, 3780, 5544, 5040, 11, 35, 168, 432, 1320, 1680, 3960, 6300, 7560, 10080, 13, 36, 198, 480, 1512, 1800, 4200, 6720, 9240, 12600, 15120 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

This is a permutation of the natural numbers.

Row 1 gives A250070.

For more information about the widths of the symmetric representation of sigma see A249351 and A250068.

The next term: 120 < T(2,4) < 360.

LINKS

Table of n, a(n) for n=1..66.

Index entries for sequences that are permutations of the natural numbers

EXAMPLE

The corner of the square array T(j,k) begins:

1,  6, 60, 120, 360, ...

2, 12, 72, ...

3, 15, 84, ...

4, 18, ...

5, 20, ...

7, ...

...

For j = 1 and k = 2; T(1,2) is the first number n such that the symmetric representation of sigma(n) has a part with maximum width 2 as shown below:

.

.      Dyck paths            Cells              Widths

.     _ _ _ _             _ _ _ _

.     _ _ _  |_          |_|_|_|_|_          / / / /

.          |   |_              |_|_|_              / /

.          |_ _  |             |_|_|_|             / / /

.              | |                 |_|                 /

.              | |                 |_|                 /

.              | |                 |_|                 /

.

The widths of the symmetric representation of sigma(6) = 12 are [1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1], also the 6th row of triangle A249351.

CROSSREFS

Cf. A000203, A196020, A235791, A236104, A237048, A237270, A237271, A237591, A237593, A245092, A249351, A250068, A250070, A250071.

Sequence in context: A054619 A054618 A120859 * A098810 A081469 A209664

Adjacent sequences:  A253255 A253256 A253257 * A253259 A253260 A253261

KEYWORD

nonn,tabl

AUTHOR

Omar E. Pol, Jul 08 2015

EXTENSIONS

More terms from Charlie Neder, Jan 11 2019

STATUS

approved

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Last modified September 21 21:58 EDT 2019. Contains 327282 sequences. (Running on oeis4.)