A053887 -id:A053887 - cp's OEIS frontend

A053886 Numbers k such that k^2 contains only digits {1,2,8}.

1, 9, 11, 91, 109, 359, 3359, 15109, 33359, 333359, 3333359, 14903989, 15127091, 28497739, 33333359, 90450109, 333333359, 3333333359, 33333333359, 46023126591, 333333333359, 1697404542909, 3333333333359, 33333333333359

Offset: 1

Patrick De Geest, Mar 15 2000

Zhao Hui Du, Table of n, a(n) for n = 1..44
Patrick De Geest, Squares containing at most three distinct digits, Index entries for related sequences
Author?, Source(txt)

Cf. A053887.

More terms from C. Ronaldo (aga_new_ac(AT)hotmail.com), Jan 03 2005

Three more terms from Jon E. Schoenfield, Sep 03 2006

A119107 Triangular numbers composed of digits {1,2,8}.

Original entry on oeis.org

1, 21, 28, 1128, 2211, 8128, 118828, 222111, 821121, 828828, 881128, 1188111, 1828828, 22221111, 28218828, 88811128, 1821212128, 2222211111, 8888111128, 222222111111, 888881111128, 22222221111111, 88888811111128, 1122211112118111, 2222222211111111

Offset: 1

Giovanni Resta, May 10 2006

Giovanni Resta, Tridigital Triangular Numbers

Cf. A000217, A053887, A119108. See A119033 for a table of cross-references.

a(n) = A000217(A119108(n)). - Michel Marcus, Mar 23 2023

a(24)-a(25) from Tyler Busby, Mar 23 2023

cp's OEIS Frontend

A053886 Numbers k such that k^2 contains only digits {1,2,8}.

Views

Author

Keywords

Links

Crossrefs

Extensions