

A108023


a(1)=2; a(n) is the smallest prime such that a(n)a(n1) is a 6th power (>0).


1



2, 3, 67, 131, 2176782467, 22485250805891, 132514367714796227, 132514373203827971, 1472610013828827971, 3552822265021773233027, 3552822910800868882883, 3552824349717606382019, 3552824349723095413763
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,1


COMMENTS

Since a(5) is 6 mod 7, all entries after a(5) are congruent to a(5) mod 14^6


LINKS

Table of n, a(n) for n=1..13.


EXAMPLE

a(4)=131 which is 2 mod 3 so if 131 +k^6 is prime, k must be divisible by 6. 131+6^6 and 131+24^6 are divisible by 13, 131 +12^6 and 131+18^6 are divisible by 5, 131+30^6 is divisible by 41, 131+36^6 is prime.


CROSSREFS

Cf. A073609, A076201.
Sequence in context: A041953 A099080 A132532 * A352163 A041249 A356795
Adjacent sequences: A108020 A108021 A108022 * A108024 A108025 A108026


KEYWORD

nonn


AUTHOR

John L. Drost, May 31 2005


EXTENSIONS

Corrected by T. D. Noe, Nov 15 2006


STATUS

approved



