A249968 Numbers whose squares remain squares when prepended with 2 and appended with 25 in base 10.

16, 14130, 42260, 491230, 11192300, 18172350, 20878660, 565802820, 592874284, 2765209166, 19789454240, 35082937167210, 393840573502266, 7027165155369334, 12621688931426416, 14721538161161584, 24823861761554840, 26825614715841966, 707326082998942734

Offset

1,1

Comments

Conjecture: squares of numbers in the sequence ends in either 00 or 56.

a(73) >= 10^50. - Hiroaki Yamanouchi, Nov 22 2014

Links

Chai Wah Wu and Hiroaki Yamanouchi, Table of n, a(n) for n = 1..72 (terms a(1)-a(62) from Chai Wah Wu)

Example

14130^2 = 199656900, 219965690025 = 469005^2.

Crossrefs

Cf. A249633, A249621.

Sequence in context: A223102 A167062 A233140 * A017188 A168576 A013831

Adjacent sequences: A249965 A249966 A249967 * A249969 A249970 A249971

Keyword

nonn,base

Author

Chai Wah Wu, Nov 09 2014

Status

approved