cp's OEIS Frontend

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.

A002650 Quintan primes: p = (x^5 + y^5)/(x + y).

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%I A002650 M4792 N2044 #29 Jan 11 2018 01:09:03
%S A002650 11,61,181,421,461,521,991,1621,1871,3001,4441,4621,6871,9091,9931,
%T A002650 12391,13421,14821,19141,25951,35281,35401,55201,58321,61681,62071,
%U A002650 72931,74731,91331,92921,95881,108421,117911,117991,131041,132661,141961
%N A002650 Quintan primes: p = (x^5 + y^5)/(x + y).
%C A002650 (x^5 + y^5)/(x + y) = x^4 - y*x^3 + y^2*x^2 - y^3*x + y^4. - _Jens Kruse Andersen_, Jul 14 2014
%D A002650 A. J. C. Cunningham, Binomial Factorisations, Vols. 1-9, Hodgson, London, 1923-1929; see Vol. 2, p. 201.
%D A002650 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
%D A002650 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H A002650 Jens Kruse Andersen, <a href="/A002650/b002650.txt">Table of n, a(n) for n = 1..10000</a>
%H A002650 A. J. C. Cunningham, <a href="/A001912/a001912.pdf">Binomial Factorisations</a>, Vols. 1-9, Hodgson, London, 1923-1929. [Annotated scans of a few pages from Volumes 1 and 2]
%e A002650 (3^5 + 1^5)/(3 + 1) = 61. This is prime and therefore in the sequence. - _Jens Kruse Andersen_, Jul 14 2014
%t A002650 Take[Select[Union[(#[[1]]^5+#[[2]]^5)/Total[#]&/@Tuples[Range[200],2]], #>0&& PrimeQ[#]&],50] (* _Harvey P. Dale_, May 21 2012 *)
%o A002650 (PARI) m=10^6; v=[]; for(x=1, (2*m)^(1/4), for(y=1, x, n=(x^5+y^5)/(x+y); if(n<=m && isprime(n), v=concat(v,n)))); vecsort(v) \\ _Jens Kruse Andersen_, Jul 14 2014
%Y A002650 Cf. A002649.
%K A002650 nonn
%O A002650 1,1
%A A002650 _N. J. A. Sloane_
%E A002650 More terms from _Sean A. Irvine_, May 08 2014