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A139092 a(n) = number of (distinct) prime divisors of (9+prime(n)!)/9. 4
3, 3, 2, 2, 2, 3, 2, 3, 4, 4, 5, 3, 3, 6, 5, 2, 3, 4, 3 (list; graph; refs; listen; history; text; internal format)
OFFSET

4,1

COMMENTS

Conjecture: all prime divisors in A139089 are distinct

LINKS

Table of n, a(n) for n=4..22.

MATHEMATICA

a = {}; Do[w = (Prime[n]! + 9)/9; AppendTo[a, w], {n, 4, 16}]; a (*Artur Jasinski*)

CROSSREFS

Cf. A082672, A089085, A089130, A117141, A007749, A139056-A139066, A020458, A139068, A137390, A139070-A139075, A136019, A136020, A136026, A136027, A139089-A139092.

Sequence in context: A133884 A065775 A096837 * A021305 A075788 A324080

Adjacent sequences:  A139089 A139090 A139091 * A139093 A139094 A139095

KEYWORD

more,nonn

AUTHOR

Artur Jasinski, Apr 08 2008

EXTENSIONS

More terms from Jon E. Schoenfield, Jul 16 2010

STATUS

approved

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Last modified June 19 19:11 EDT 2019. Contains 324222 sequences. (Running on oeis4.)