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A247267
Square numbers not divisible by 100 that remain square when their most-significant (or leftmost) digit is removed.
2
1, 4, 9, 49, 64, 81, 225, 625, 1225, 2025, 3025, 4225, 5625, 7225, 9025, 15625, 27225, 30625, 34225, 42025, 50625, 60025, 70225, 75625, 81225, 93025, 105625, 275625, 330625, 600625, 893025, 950625, 970225, 1050625, 2030625, 3330625, 4950625, 9455625, 9765625, 15405625
OFFSET
1,2
COMMENTS
Subsequence of A225885. It is easy to see that the multiples of 100 in A225885 are earlier entries of the sequence multiplied by 100, so this sequence removes this redundancy in some sense. It appears that all entries in A225885 after the first 3 entries ends in either 25 or 00, so this sequence appears to end in 25 after the first 3 entries.
PROG
(PARI) for(n=10, 10^6, if(n%100, if(issquare(n)&&issquare(n%(10^(#Str(n)-1))), print1(n, ", ")))) \\ Derek Orr, Nov 01 2014
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Chai Wah Wu, Nov 01 2014
EXTENSIONS
Added 1, 4, 9 to sequence to match A225885 - Chai Wah Wu, Nov 03 2014
STATUS
approved