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A171771
Primes of form n^6-(n+1)^5.
2
971, 431441, 838949, 2614691, 6770161, 43845881, 570523321, 9244951889, 33640090481, 41402933641, 81303824909, 126165366289, 137240997911, 346860978491, 372445245449, 525200678549, 726938163649, 774170449439
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OFFSET
1,1
COMMENTS
(1) It is conjectured that sequence is infinite.
(2) p=97=prime(25) is the smallest prime such that (p-1)^6-p^5 and p^6-(p+1)^5 are primes.
REFERENCES
Leonard E. Dickson: History of the Theory of numbers, vol. I, Dover Publications 2005
Derrick H. Lehmer, Guide to Tables in the Theory of Numbers Washington, D.C. 1941
LINKS
Harvey P. Dale,
Table of n, a(n) for n = 1..1000
EXAMPLE
4^6-5^5=971 and 9^6-10^5=431441 are prime.
MATHEMATICA
Select[Table[n^6-(n+1)^5, {n, 3, 100}], PrimeQ] (*
Harvey P. Dale
, Mar 06 2019 *)
CROSSREFS
Cf.
A002327
,
A140719
,
A087191
Sequence in context:
A257975
A217161
A243861
*
A206089
A217162
A203375
Adjacent sequences:
A171768
A171769
A171770
*
A171772
A171773
A171774
KEYWORD
nonn
AUTHOR
Ulrich Krug (leuchtfeuer37(AT)gmx.de), Dec 18 2009
EXTENSIONS
Edited by
D. S. McNeil
, Nov 21 2010
STATUS
approved