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.

A123134 a(n) = prime(n)*(prime(n+1) + 1).

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%I A123134 #29 Sep 08 2022 08:45:28
%S A123134 8,18,40,84,154,234,340,456,690,928,1178,1554,1804,2064,2538,3180,
%T A123134 3658,4148,4824,5254,5840,6636,7470,8722,9894,10504,11124,11770,12426,
%U A123134 14464,16764,18078,19180,20850,22648,23858,25748,27384,29058,31140,32578
%N A123134 a(n) = prime(n)*(prime(n+1) + 1).
%C A123134 All terms are even. - _Michel Marcus_, Apr 02 2017
%H A123134 G. C. Greubel, <a href="/A123134/b123134.txt">Table of n, a(n) for n = 1..1000</a>
%H A123134 A. Frank & P. Jacqueroux, <a href="http://www.paulcooijmans.com/others/intcontest.pdf">International Contest</a>, 2001. Item 21
%F A123134 a(n) = A000040(n)*A008864(n+1). - _Zak Seidov_, Apr 02 2017
%F A123134 a(n) = A286624(n) - 1. - _Antti Karttunen_, Jul 06 2017
%e A123134 a(1) = 2*(3+1) = 8, a(2) = 3*(5+1) = 18, a(3) = 5*(7+1) = 40, ...
%t A123134 a[n_]:=Prime[n](Prime[n+1]+1); Array[a, 80] (* _Giovanni Resta_, Apr 02 2017 *)
%t A123134 #[[1]](#[[2]]+1)&/@Partition[Prime[Range[50]],2,1] (* _Harvey P. Dale_, Jan 06 2019 *)
%o A123134 (PARI) for(n=1,100,print1(prime(n)*(prime(n+1)+1),","))
%o A123134 (Python)
%o A123134 from sympy import prime
%o A123134 def a(n): return prime(n) * (prime(n + 1) + 1) # _Indranil Ghosh_, Apr 02 2017
%o A123134 (Magma) [NthPrime(n)*(NthPrime(n+1) +1): n in [1..40]]; // _G. C. Greubel_, Aug 04 2021
%Y A123134 Cf. A000040, A008864, A286624.
%K A123134 nonn
%O A123134 1,1
%A A123134 Herman Jamke (hermanjamke(AT)fastmail.fm), Sep 30 2006