A053951 Squares composed of digits {4,5,7}.

4, 7744, 47444544, 47775744, 57577744, 4755757444, 44547775545744, 7557757477754457744, 55744775754747577744, 74474545477575775744575745574544, 747554745554544455555455747745774457774554454557445577744

Offset

1,1

Links

Table of n, a(n) for n=1..11.

Author?, Source(txt)

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

H. Mishima, Sporadic tridigital solutions

Formula

a(n) = A053950(n)^2.

Crossrefs

Cf. A053950.

Sequence in context: A304994 A058440 A058464 * A058460 A115050 A072724

Adjacent sequences: A053948 A053949 A053950 * A053952 A053953 A053954

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

One more term from Mishima's webpage added by Max Alekseyev, Jan 28 2012

a(11) from Zhao Hui Du, Mar 10 2024

Status

approved