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A261210 a(n) = gpf(1 + Product_{k=0..4} prime(n+k)), where gpf is greatest prime factor and prime(i) is the i-th prime. 1
2311, 1877, 163, 80831, 12647, 6967, 139, 3633983, 1657, 15473, 2970049, 933853, 64776587, 99767, 21067, 84961, 1524137, 820319, 157229, 489427, 2066140207, 71899, 15287, 1680583, 769117, 55732973, 52889, 225941, 4678959379, 1491686591, 87701 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Anders Hellström, Table of n, a(n) for n = 1..1000

FORMULA

a(n) = A006530(1+A046303(n)). - Michel Marcus, Aug 13 2015

MATHEMATICA

Array[FactorInteger[1 + Product[Prime[# + k], {k, 0, 4}]][[-1, 1]] &, {31}] (* Michael De Vlieger, Aug 19 2015 *)

PROG

(PARI) gpf(n)=vecmax(factor(n)[, 1]);

first(m)=vector(m, i, gpf(1+prod(j=0, 4, prime(i+j))));

CROSSREFS

Cf. A006530, A046303.

Sequence in context: A046403 A288072 A087978 * A020435 A288798 A035893

Adjacent sequences:  A261207 A261208 A261209 * A261211 A261212 A261213

KEYWORD

nonn

AUTHOR

Anders Hellström, Aug 12 2015

STATUS

approved

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Last modified August 4 02:24 EDT 2021. Contains 346441 sequences. (Running on oeis4.)