

A019544


Squares whose digits are squares.


9



0, 1, 4, 9, 49, 100, 144, 400, 441, 900, 1444, 4900, 9409, 10000, 10404, 11449, 14400, 19044, 40000, 40401, 44100, 44944, 90000, 144400, 419904, 490000, 491401, 904401, 940900, 994009, 1000000, 1004004, 1014049, 1040400, 1100401, 1144900, 1440000, 1904400
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OFFSET

1,3


COMMENTS

Are there infinitely many terms not divisible by 100?  Charles R Greathouse IV, Sep 19 2012
Yes. For example, the squares of the type (k*10^m+1)^2, where m>0 and k = 2, 70, 970, 202470000 or m>1 and k = 10^m3, belong to the sequence.  Bruno Berselli, Jan 10 2013


LINKS

Robert Israel, Table of n, a(n) for n = 1..544
Sylvester Smith, A Set of Conjectures on Smarandache Sequences, Bulletin of Pure and Applied Sciences, (Bombay, India), Vol. 15 E (No. 1), 1996, pp. 101107.
Eric Weisstein's World of Mathematics, Smarandache Sequences


FORMULA

a(n) = A285550(n)^2.  Alois P. Heinz, Apr 21 2017


MAPLE

filter:= n > convert(convert(n, base, 10), set) subset {0, 1, 4, 9}:
select(filter, [seq(n^2, n=1..10^5)]); # Robert Israel, Aug 14 2018


PROG

(MAGMA) [n^2: n in [0..2000]  forall{d: d in Intseq(n^2)  d in [0, 1, 4, 9]}]; // Bruno Berselli, Jan 10 2013


CROSSREFS

Cf. A285550.
Sequence in context: A055812 A268099 A061867 * A053059 A006716 A068809
Adjacent sequences: A019541 A019542 A019543 * A019545 A019546 A019547


KEYWORD

nonn,base


AUTHOR

R. Muller


EXTENSIONS

Offset changed to 1 by Alois P. Heinz, Apr 21 2017


STATUS

approved



