A128947 Main diagonal of polygonal lucky array defined in A128511.

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

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 A357768

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