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Search: id:A121616
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| A121616 |
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Nexus primes of order 5 or primes of form n^5 - (n-1)^5 = A022521[n-1]. |
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6
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| 31, 211, 4651, 61051, 371281, 723901, 1803001, 2861461, 4329151, 4925281, 7086451, 7944301, 14835031, 19611901, 23382031, 44119351, 54664711, 86548801, 97792531, 162478501, 189882031, 267217051, 293109961, 306740281, 490099501
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OFFSET
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1,1
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COMMENT
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Indices n such that Nexus number of order 5 (or A022521[n-1] = n^5 - (n-1)^5) is prime are listed in A121617[n] = {2,3,6,11,17,20,25,28,31,32,35,36,42,45,47,55,58,65,67,76,79,86,88,89,100,...}. Last digit is always 1 because 5 is Pythagorean prime A002144[1]. a(1) = 31 is Mersenne prime A000668[3].
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LINKS
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Zak Seidov, Table of n, a(n) for n = 1..2000.
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MATHEMATICA
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Select[Table[n^5 - (n-1)^5, {n, 1, 200}], PrimeQ]
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CROSSREFS
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Cf. A022521, A000040, A000043, A002144, A000668, A002407, A121617, A121618, A121619, A121620.
Sequence in context: A142328 A022521 A090027 this_sequence A062393 A042874 A001136
Adjacent sequences: A121613 A121614 A121615 this_sequence A121617 A121618 A121619
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KEYWORD
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nonn
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AUTHOR
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Alexander Adamchuk (alex(AT)kolmogorov.com), Aug 10 2006
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