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A128947 Main diagonal of polygonal lucky array defined in A128511. 0
1, 9, 477, 2415, 2059, 2133, 651, 2835, 14935, 23529, 35721, 58311, 27105, 24013, 167775, 49375, 92925, 193305, 273105, 238855, 850155, 94209, 395901, 1055241, 310233, 387001, 1492839, 540765, 731025, 2172081, 934431, 835621 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Main diagonal of array T(k,n) = n-th lucky number which is also a (k+3)-gonal number, for nonnegative k, whose zeroth, first, second rows are: A118565 Numbers which are both lucky and triangular. A031162 Numbers that are both lucky and square. A128511 Numbers which are both lucky and pentagonal.

LINKS

Table of n, a(n) for n=1..32.

EXAMPLE

Array begins:

k..|.n-th lucky number which is also a (k+3)-gonal number

0..|.1...3...15....21...105...171...231...741...903..1275.

1..|.1...9...25....49...169...289...361...529...729...841.

2..|.1..51..477...651...925..2625..5551..6501..9801.17767.

3..|.1..15..231..2415..3003..3655..5151.10585.11781.13695.

4..|.1...7..189...235..2059..6175..8037..9211.17935.23377.

5..|.1..21..133...645..1281..2133..2821..4033..4485..7701.

6..|.1...9...75...111...261...559...651..1491..1639..2125.

7..|.1.297..451...855..1105..1387..1701..2835..4257..5967.

PROG

(PARI) findpl(vl, n) = {nb = 0; for (i=1, #vl, if (ispolygonal(vl[i], n+2), nb++; if (nb == n, return (vl[i]))); ); }

lista(nn) = {vl = readvec("b000959.log"); for (n=1, nn, print1(findpl(vl, n), ", "); ); } \\ Michel Marcus, Mar 04 2014

CROSSREFS

Cf. A000567, A000959, A031162, A118565, A128511.

Sequence in context: A289054 A166879 A213447 * A293951 A267236 A306820

Adjacent sequences:  A128944 A128945 A128946 * A128948 A128949 A128950

KEYWORD

more,nonn

AUTHOR

Jonathan Vos Post, May 09 2007, May 23 2007

EXTENSIONS

More terms from R. J. Mathar, Jun 07 2007

6 more terms via b000959.txt from R. J. Mathar, Oct 22 2010

a(21)-a(32) via b000959.txt from Michel Marcus, Mar 04 2014

STATUS

approved

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Last modified February 24 13:05 EST 2020. Contains 332209 sequences. (Running on oeis4.)