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A102245
Number of distinct prime factors of prime p concatenated p+1 times.
1
3, 3, 6, 5, 10, 8, 11, 11, 13, 20, 15, 6, 21, 15, 22, 18, 26
OFFSET
1,1
EXAMPLE
At p=2, the number of distinct prime factors of 222 is 3.
At p=3, the number of distinct prime factors of 3333 is 3.
At p=5, the number of distinct prime factors of 555555 is 6.
At p=7, the number of distinct prime factors of 77777777 is 5.
MATHEMATICA
f[n_] := Length[ FactorInteger[ FromDigits[ Flatten[ Table[ IntegerDigits[ Prime[n]], {Prime[n] - 1}]] ]]]; Table[ f[n], {n, 17}] (* Robert G. Wilson v, Feb 21 2005 *)
CROSSREFS
Sequence in context: A257143 A080512 A225441 * A038167 A307967 A131077
KEYWORD
nonn,base
AUTHOR
Parthasarathy Nambi, Feb 18 2005
EXTENSIONS
More terms from Robert G. Wilson v, Feb 21 2005
STATUS
approved