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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A228033 Primes of the form 8^k + 5.

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%I A228033 #38 Jul 24 2025 03:26:56
%S A228033 13,2787593149816327892691964784081045188247557,
%T A228033 15177100720513508366558296147058741458143803430094840009779784451085189728165691397
%N A228033 Primes of the form 8^k + 5.
%C A228033 a(4) = 8^64655 + 5 = 1.919...*10^58389 is too large to include. - _Amiram Eldar_, Jul 23 2025
%t A228033 Select[Table[8^n + 5, {n, 4000}], PrimeQ]
%o A228033 (Magma) [a: n in [1..300] | IsPrime(a) where a is 8^n+5];
%Y A228033 Cf. A217355 (associated n).
%Y A228033 Cf. Primes of the form k^n + h: A092506 (k=2, h=1), A057733 (k=2, h=3), A123250 (k=2, h=5), A104066 (k=2, h=7), A104070 (k=2, h=9), A057735 (k=3, h=2), A102903 (k=3, h=4), A102870 (k=3, h=8), A102907 (k=3, h=10), A290200 (k=4, h=1), A182330 (k=5, h=2), A102910 (k=5, h=8), A182331 (k=6, h=1), A104118 (k=6, h=5), A104115 (k=6, h=7), A104065 (k=7, h=4), this sequence (k=8, h=5), A144360 (k=8, h=7), A145440 (k=8, h=9), A228034 (k=9, h=2), A159352 (k=10, h=3), A159031 (k=10, h=7).
%K A228033 nonn,hard,bref
%O A228033 1,1
%A A228033 _Vincenzo Librandi_, Aug 11 2013