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A157464
Number of distinct squares when inserting at most one digit in decimal representation of n.
3
4, 3, 1, 1, 3, 1, 3, 0, 1, 2, 1, 1, 1, 0, 1, 0, 3, 0, 0, 2, 0, 1, 1, 0, 1, 4, 1, 0, 1, 3, 0, 1, 1, 0, 1, 0, 2, 0, 0, 0, 1, 2, 0, 0, 3, 0, 0, 0, 1, 1, 0, 0, 1, 0, 0, 0, 2, 1, 0, 1, 0, 2, 1, 0, 1, 1, 1, 1, 0, 1, 0, 0, 1, 0, 1, 0, 2, 0, 1, 1, 0, 2, 0, 0, 3, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 2, 0, 0, 0, 3, 0, 1, 0, 1
OFFSET
0,1
COMMENTS
a(A157465(n)) > 0; a(A000290(n)) > 0.
LINKS
EXAMPLE
a(25) = #{25=5^2, 225=15^2, 256=16^2, 625=25^2} = 4;
a(26) = #{256=16^2} = 1;
a(27) = #{} = 0;
a(28) = #{289=17^2} = 1;
a(29) = #{289=17^2, 529=23^2, 729=27^2} = 3.
MATHEMATICA
Join[{4}, Table[Count[Union[Flatten[Table[FromDigits[Insert[IntegerDigits[n], d, m]], {d, 0, 9}, {m, IntegerLength[n]+1}]]], _?(IntegerQ[Sqrt[#]]&)], {n, 110}]] (* Harvey P. Dale, Sep 12 2021 *)
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Reinhard Zumkeller, Mar 01 2009
STATUS
approved