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A053608
Numbers x = LCM(1,2,...,k) such that x^2 + 1 is prime.
1
1, 2, 6, 420, 360360, 718766754945489455304472257065075294400
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OFFSET
1,2
COMMENTS
The next term has k > 10^4, if it exists. - Amiram Eldar, Aug 23 2024
LINKS
Table of n, a(n) for n=1..6.
MATHEMATICA
Select[FoldList[LCM, 1, Select[Range[100], PrimePowerQ]], PrimeQ[#^2 + 1] &] (* Amiram Eldar, Aug 23 2024 *)
CROSSREFS
Cf. A003418, A049536, A046029, A051418, A051451, A051739, A053609.
Sequence in context: A092024 A252741 A069261 * A199239 A123261 A124061
Adjacent sequences: A053605 A053606 A053607 * A053609 A053610 A053611
KEYWORD
nonn,hard
AUTHOR
Labos Elemer, Feb 09 2000
STATUS
approved

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Last modified October 5 09:33 EDT 2024. Contains 376531 sequences.
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