A053898 Numbers k such that k^2 contains only digits {1,4,7}.

1, 2, 12, 21, 38, 88, 2729, 2036462, 2678521, 1203108962, 343143082067979, 2678520388463521, 1071033028175028538, 2177492084289725902412

Offset

1,2

Links

Table of n, a(n) for n=1..14.

Author?, Source(txt) [Broken link]

P. De Geest, Squares containing at most three distinct digits, Index entries for related sequences

H. Mishima, Sporadic tridigital solutions

Mathematica

Select[Range[1, 10000], ContainsOnly[IntegerDigits[#^2], {1, 4, 7}] &] (* Julien Kluge, Jul 08 2016 *)

Crossrefs

Cf. A053899.

Sequence in context: A279424 A073041 A284595 * A058413 A053890 A053896

Adjacent sequences: A053895 A053896 A053897 * A053899 A053900 A053901

Keyword

nonn,base,more

Author

Patrick De Geest, Mar 15 2000

Extensions

More terms from C. Ronaldo (aga_new_ac(AT)hotmail.com), Jan 04 2005

Four more terms from Mishima's webpage added by Max Alekseyev, Jan 28 2012

Status

approved