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A108728 Number of distinct prime divisors of concatenated even numbers. 0
1, 2, 3, 2, 5, 3, 2, 3, 6, 5, 3, 4, 6, 4, 5, 4, 3, 5, 4, 7, 6, 5, 8, 3, 7, 4, 4, 8, 5, 7, 4, 4, 8, 5, 7, 6, 4, 8, 8, 7, 5, 3 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..42.

EXAMPLE

Number of distinct prime divisors of 2 is 1 - which is the first term.

Number of distinct prime divisors of 24 is 2 - which is the second term.

Number of distinct prime divisors of 246 is 3 - which is the third term.

CROSSREFS

Cf. A019520.

Sequence in context: A007967 A054494 A112764 * A049805 A104887 A064886

Adjacent sequences:  A108725 A108726 A108727 * A108729 A108730 A108731

KEYWORD

nonn,base

AUTHOR

Parthasarathy Nambi, Jun 21 2005

STATUS

approved

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Last modified December 5 21:40 EST 2016. Contains 278771 sequences.