A087019 Lunar squares: n*n where * is lunar multiplication (A087062).

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 100, 111, 112, 113, 114, 115, 116, 117, 118, 119, 200, 211, 222, 223, 224, 225, 226, 227, 228, 229, 300, 311, 322, 333, 334, 335, 336, 337, 338, 339, 400, 411, 422, 433, 444, 445, 446, 447, 448, 449, 500, 511, 522, 533, 544, 555, 556, 557, 558

Offset: 0

Author

Marc LeBrun and N. J. A. Sloane, Oct 19 2003

Keywords

• nonn
• base

Comments

Sequence is not monotonic (1011*1011 = 1011111 > 1020*1020 = 1010200). In fact it even contains repetitions (11011*11011 = 11111*11111 = 111111111). See A172199. - N. J. A. Sloane, Dec 20 2010

Links

• N. J. A. Sloane, Table of n, a(n) for n = 0..10000
• D. Applegate, C program for lunar arithmetic and number theory, [Note: we have now changed the name from "dismal arithmetic" to "lunar arithmetic" - the old name was too depressing]
• D. Applegate, M. LeBrun and N. J. A. Sloane, Dismal Arithmetic, arXiv:1107.1130 [math.NT], 2011. [Note: we have now changed the name from "dismal arithmetic" to "lunar arithmetic" - the old name was too depressing]
• D. Applegate, M. LeBrun, N. J. A. Sloane, Dismal Arithmetic, J. Int. Seq. 14 (2011) # 11.9.8.
• Brady Haran and N. J. A. Sloane, Primes on the Moon (Lunar Arithmetic), Numberphile video, Nov 2018.
• Christian Woll, There is a 3X3 Magic Square of Squares on the Moon - A Lot of Them, Actually, arXiv:1811.04923 [math.HO], 2018.
• Index entries for sequences related to dismal (or lunar) arithmetic

Crossrefs

Cf. A087062 (lunar product), A087097 (lunar primes).

Cf. A172199, A180513, A181319, A087097.

Programs

PARI

apply( A087019(n)=A087062(n,n), [1..60]) \\ M. F. Hasler, Nov 15 2018

Formula

a(n)=A087062(n,n). - M. F. Hasler, Nov 15 2018