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.
a(1)=1 because 3^4 = 81 = 1 mod 2 a(2)=2 because 5^4 = 625 = 1 mod 3
Table[Mod[Prime[n]^4, Prime[n - 1]], {n, 2, 50}]
a(1)=1 because 3^5 = 243 = 1 mod 2 a(2)=2 because 5^5 = 3125 = 2 mod 3
Table[Mod[Prime[n]^5, Prime[n - 1]], {n, 2, 50}]
a(1)=1 because 3^6 = 729 = 1 mod 2 a(2)=2 because 5^6 = 15625 = 1 mod 3
Table[Mod[Prime[n]^6, Prime[n - 1]], {n, 2, 50}]
a(1)=1 because 3^7 = 1 mod 2 a(2)=2 because 5^7 = 2 mod 3
[NthPrime(n)^7 mod NthPrime(n-1): n in [2..50]]; // Bruno Berselli, May 23 2011
seq(ithprime(n)&^7 mod ithprime(n-1),n=2..100); # Robert Israel, Feb 12 2020
Table[Mod[Prime[n]^7, Prime[n - 1]], {n, 2, 50}]
(* The following program is more efficient because it only generates each prime once, but it is less easy to understand: *)
PowerMod[Last[#],7,First[#]]&/@Partition[Prime[Range[60]],2,1] (* Harvey P. Dale, Sep 02 2016 *)
a(n) = my(p=prime(n)); lift(Mod(p, precprime(p-1))); \\ Michel Marcus, Mar 17 2023
a(1)=1 because 3^8 = 1 mod 2 a(2)=2 because 5^8 = 1 mod 3
Table[Mod[Prime[n]^8, Prime[n - 1]], {n, 2, 50}]
PowerMod[#[[2]],8,#[[1]]]&/@Partition[Prime[Range[70]],2,1] (* Harvey P. Dale, Nov 05 2014 *)
a(1)=1 because 3^9 = 1 mod 2 a(2)=2 because 5^9 = 2 mod 3
Table[Mod[Prime[n]^9, Prime[n - 1]], {n, 2, 50}]
PowerMod[Last[#],9,First[#]]&/@Partition[Prime[Range[50]],2,1] (* Harvey P. Dale, Aug 16 2013 *)
a(1)=1 because 3^10 = 1 mod 2 a(2)=2 because 5^10 = 1 mod 3
Table[Mod[Prime[n]^10, Prime[n - 1]], {n, 2, 50}]
PowerMod[Last[#],10,First[#]]&/@Partition[Prime[Range[50]],2,1] (* Harvey P. Dale, Apr 17 2014 *)
a(1)=1 because 3^11 = 1 mod 2 a(2)=2 because 5^11 = 2 mod 3
Table[Mod[Prime[n]^11, Prime[n - 1]], {n, 2, 50}]
PowerMod[Last[#],11,First[#]]&/@Partition[Prime[Range[100]],2,1] (* Harvey P. Dale, Apr 04 2013 *)
a(1)=1 because 3^12 = 1 mod 2 a(2)=2 because 5^12 = 1 mod 3
Table[Mod[Prime[n]^12, Prime[n - 1]], {n, 2, 50}]
[Floor((NthPrime(n))^3/(n*Log(n))): n in [2..60]]; // Vincenzo Librandi, Jul 03 2015
Table[Floor[Prime[n]^3/(n Log[n])], {n, 2, 30}]
a(n) = floor(prime(n)^3/(n*log(n))); \\ Michel Marcus, Jul 02 2015
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