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A109073
Number of decimal digits ( counted with multiplicity ) in n^2 but not in n.
0
0, 0, 1, 1, 2, 1, 1, 2, 2, 2, 0, 1, 2, 2, 2, 2, 2, 3, 3, 2, 1, 2, 3, 2, 3, 1, 1, 1, 2, 3, 1, 2, 3, 4, 4, 3, 3, 3, 4, 4, 2, 2, 3, 3, 4, 3, 3, 4, 3, 3, 1, 3, 3, 4, 4, 3, 3, 4, 4, 4, 1, 3, 4, 2, 2, 3, 3, 4, 3, 3, 2, 3, 4, 3, 2, 2, 1, 4, 3, 4, 2, 3, 3, 2, 4, 3, 3, 3, 4, 3, 2, 3, 4, 3, 4, 2, 2, 2, 3, 3, 0, 1, 2, 2, 2
OFFSET
0,5
COMMENTS
Cf. A076493 Number of common and distinct decimal digits of n and n^2, A109071 Number of common decimal digits ( counted with multiplicity ) of n and n^2, A109072 Number of decimal digits ( counted with multiplicity ) in n but not in n^2.
EXAMPLE
a(35)=4 because 34^2=1156 and there are 4 digits (counted with multiplicity) which are in 34^2 but not in 34.
MATHEMATICA
UnsortedComplement[x_List, y__List]:=Replace[x, Dispatch[(#\[RuleDelayed]Sequence[])&/@Union[y]], 1]; Table[Length[UnsortedComplement[IntegerDigits[n], IntegerDigits[n^2]]], {n, 0, 200}]
CROSSREFS
KEYWORD
base,easy,nonn
AUTHOR
Zak Seidov, Jun 20 2005
STATUS
approved