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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

Chai Wah Wu, Table of n, a(n) for n = 1..1185

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

Cf. A225885, A247885. A249587.

Sequence in context: A013495 A164839 A225885 * A115687 A115711 A029791

Adjacent sequences:  A247264 A247265 A247266 * A247268 A247269 A247270

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 May 28 01:34 EDT 2020. Contains 334671 sequences. (Running on oeis4.)