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A238746 Number of distinct prime signatures that occur among the divisors of the n-th prime signature number (A025487(n)). 2
1, 2, 3, 3, 4, 5, 5, 7, 4, 6, 6, 9, 7, 7, 9, 11, 10, 8, 12, 9, 13, 5, 10, 13, 9, 15, 14, 15, 9, 14, 16, 10, 18, 19, 17, 13, 18, 10, 19, 11, 16, 21, 12, 15, 24, 19, 17, 22, 16, 22, 12, 23, 24, 6, 19, 20, 29, 21, 21, 26, 22, 25, 13, 30, 27, 11, 26, 25, 19, 34 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Also the number of members of A025487 that divide A025487(n).

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = A085082(A025487(n)) = A085082(A181822(n)).

EXAMPLE

5 members of A025487 divide A025487(6) = 12 (namely, 1, 2, 4, 6 and 12); therefore, a(6) = 5.

CROSSREFS

Cf. A085082, A025487, A181822.

Rearrangement of A115728, A115729 and A238690.

A116473(n) is the number of times n appears in the sequence.

Sequence in context: A127039 A143091 A114539 * A272611 A156562 A290736

Adjacent sequences:  A238743 A238744 A238745 * A238747 A238748 A238749

KEYWORD

nonn

AUTHOR

Matthew Vandermast, Apr 28 2014

STATUS

approved

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Last modified June 6 18:59 EDT 2020. Contains 334832 sequences. (Running on oeis4.)