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A331543 Squares using only decimal digits 0,1,2,3. 1
0, 1, 100, 121, 10000, 10201, 12100, 12321, 22201, 123201, 130321, 1000000, 1002001, 1020100, 1022121, 1210000, 1212201, 1232100, 1320201, 2220100, 3101121, 12320100, 13032100, 100000000, 100020001, 100200100, 100220121, 102010000, 102030201, 102212100, 102232321, 103002201, 121000000, 121022001, 121220100 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

If n is a member then so is 100*n.

All terms == 0, 1, 100, 121, 201 or 321 (mod 1000).

LINKS

Robert Israel, Table of n, a(n) for n = 1..400

EXAMPLE

a(3) = 100 is a member because 100 = 10^2 and 100 has no digits > 3.

MAPLE

Res:= NULL: count:= 0:

for k from 0 while count < 50 do

  for j in [0, 1, 100, 121, 201, 321] do

    L:= convert(k, base, 4);

    x:= add(L[i]*10^(i-1), i=1..nops(L))*1000+j;

    if issqr(x) then count:= count+1; Res:= Res, x fi

od od:

Res;

CROSSREFS

Cf. A030174.

Sequence in context: A071987 A095633 A228103 * A063009 A066139 A037139

Adjacent sequences:  A331540 A331541 A331542 * A331544 A331545 A331546

KEYWORD

nonn,base

AUTHOR

Robert Israel, Jan 19 2020

STATUS

approved

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Last modified September 28 00:46 EDT 2021. Contains 347698 sequences. (Running on oeis4.)