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A053965
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Squares composed of digits {4,7,9}.
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1
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OFFSET
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1,1
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LINKS
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FORMULA
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MATHEMATICA
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Table[Select[FromDigits/@Tuples[{4, 7, 9}, n], IntegerQ[Sqrt[#]]&], {n, 20}]//Flatten (* Harvey P. Dale, Mar 07 2018 *)
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PROG
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(Python)
from itertools import product
from sympy import integer_nthroot
for l in range(1, 21):
for p in product(*['479']*l):
n = int(''.join(p))
if integer_nthroot(n, 2)[1]:
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CROSSREFS
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KEYWORD
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nonn,base,more
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AUTHOR
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EXTENSIONS
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More terms from C. Ronaldo (aga_new_ac(AT)hotmail.com), Jan 03 2005
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STATUS
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approved
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