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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 (list; graph; refs; listen; history; text; internal format)
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.
LINKS
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
Sequence in context: A013495 A164839 A225885 * A115687 A115711 A029791
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

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Last modified March 28 15:58 EDT 2024. Contains 371254 sequences. (Running on oeis4.)