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A250433
Numbers whose squares remain squares when prepended with 7 and appended with 25 in base 10.
3
260355890, 507772957604920, 138060730605508232231178662796610, 41659593852939906475539587793151784, 849684968293046546038644821334016760090110
OFFSET
1,1
EXAMPLE
260355890^2 = 67785189457692100, 76778518945769210025 = 8762335245^2.
KEYWORD
nonn,base,more
AUTHOR
Chai Wah Wu, Nov 23 2014
EXTENSIONS
a(5) from Chai Wah Wu, Jul 20 2017
STATUS
approved