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A259020 Numbers n such that n^2 + 1 is a divisorial prime (A258455). 2
1, 6, 10, 14, 26, 74, 94, 134, 146, 206, 314, 326, 386, 466, 576, 634, 674, 1094, 1174, 1294, 1306, 1354, 1366, 1546, 1654, 1766, 1774, 1894, 1966, 2026, 2126, 2174, 2326, 2594, 2654, 2746, 2916, 2974, 2986, 3046, 3106, 3134, 3136, 3214, 3254, 3274, 3314, 3326 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
The divisorial primes are primes of the form p = 1 + Product_{d|k} d = 1 + A007955(k) for some k.
Supersequence of A259021. Subsequence of A005574. First deviation from A259021 is at a(15).
LINKS
EXAMPLE
The number 6 is in sequence because prime 37 = 6^2 + 1 is prime of the form p = 1 + Product_{d|k} d = 1 + A007955(k) for k = 6.
PROG
(Magma) Set(Sort([1] cat [Floor(Sqrt(&*(Divisors(n)))): n in [3..10000] | IsPrime(&*(Divisors(n))+1)]))
CROSSREFS
Sequence in context: A315239 A119623 A129119 * A259021 A171251 A074980
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Sep 01 2015
STATUS
approved

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Last modified June 23 10:38 EDT 2024. Contains 373643 sequences. (Running on oeis4.)