A139091 a(n) = largest prime divisor of the number prime(n)!/9 + 1.

17, 827, 22319071, 1718296754087, 35662591735219, 477262171871, 1609727002420791262479701, 146215297537890243023, 2020914387433686758547638152441, 1073774770807266077323

Offset: 4

Author

Artur Jasinski, Apr 08 2008

Keywords

• nonn

Links

• Amiram Eldar, Table of n, a(n) for n = 4..26

Crossrefs

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

Programs

Mathematica

a = {}; Do[w = FactorInteger[(Prime[n]! + 9)/9]; AppendTo[a, Last[w][[1]]], {n, 4, 16}]; a