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A053889 Squares composed of digits {1,2,9}. 2
1, 9, 121, 29929, 9991921, 1212919929, 1929229929, 1991212129, 2929299129, 1229129212921, 92222199291121, 219992999929921, 99221129991291219129, 2291192212129911919221121, 9992221299191112291912929211222129, 211192199129121999192121999211919121 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..16.

Author?, Source(txt)

P. De Geest, Squares containing at most three distinct digits, Index entries for related sequences

H. Mishima, Squares consisting of 3 different digits

MATHEMATICA

Flatten[Table[Select[FromDigits/@Tuples[{1, 2, 9}, n], IntegerQ[Sqrt[#]]&], {n, 12}]] (* This program generates only the first 9 terms of the sequence *) (* Harvey P. Dale, Oct 19 2011 *)

CROSSREFS

Cf. A053888.

Sequence in context: A045976 A276256 A276095 * A295372 A293284 A087584

Adjacent sequences:  A053886 A053887 A053888 * A053890 A053891 A053892

KEYWORD

nonn,base

AUTHOR

Patrick De Geest, Mar 15 2000

EXTENSIONS

More terms from C. Ronaldo (aga_new_ac(AT)hotmail.com), Jan 04 2005

One more term from Jon E. Schoenfield, Sep 03 2006

Two more terms from Mishima's webpage added by Max Alekseyev, Jun 17 2011

STATUS

approved

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Last modified July 30 12:39 EDT 2021. Contains 346359 sequences. (Running on oeis4.)