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 = {}; Do[If[PrimeQ[(n! + 6)/6], AppendTo[a, (n! + 6)/6]], {n, 1, 50}]; a
for(k=3,1e3,if(ispseudoprime(t=k!/6+1),print1(t", "))) \\ Charles R Greathouse IV, Jul 15 2011
a = {}; Do[If[PrimeQ[(n! + 7)/7], AppendTo[a, (n! + 7)/7]], {n, 1, 50}]; a
for(k=7,1e3,if(ispseudoprime(t=k!/7+1),print1(t", "))) \\ Charles R Greathouse IV, Jul 15 2011
Table[(Prime[n]! + 4)/4, {n, 3, 30}]
a = {}; Do[m = 1; While[ ! IntegerQ[(n + Prime[m]!)/n], m++ ]; AppendTo[a, (n + Prime[m]!)/n], {n, 1, 100}]; a (*Artur Jasinski*)
[p: p in PrimesUpTo(10^6) | Set(Intseq(p)) subset [3, 4, 2]]; // Vincenzo Librandi, Jul 28 2015
Select[Prime[Range[10^5]], Complement[IntegerDigits[#], {3, 4, 2}]=={}&] (* Vincenzo Librandi, Jul 28 2015 *)
Table[Select[FromDigits/@Tuples[{2,3,4},n],PrimeQ],{n,6}]//Flatten (* Harvey P. Dale, Nov 06 2019 *)
a(n, list=0, L=[2, 3, 4], reqpal=0)={my(t); for(d=1, 1e9, u=vector(d, i, 10^(d-i))~; forvec(v=vector(d, i, [1+(i==1&!L[1]), #L]), isprime(t=vector(d, i, L[v[i]])*u)||next; reqpal & !isprime(A004086(t)) & next; list & print1(t", "); n--||return(t)))}
[p: p in PrimesUpTo(300000) | Set(Intseq(p)) subset [2,3,6]];
Select[Prime[Range[3 10^4]], Complement[IntegerDigits[#], {2, 3, 6}]=={} &]
[p: p in PrimesUpTo(300000) | Set(Intseq(p)) subset [2, 3, 8]];
Select[Prime[Range[3 10^4]], Complement[IntegerDigits[#], {2, 3, 8}]=={} &]
[p: p in PrimesUpTo(300000) | Set(Intseq(p)) subset [2, 3, 9]];
Select[Prime[Range[4 10^3]], Complement[IntegerDigits[#], {2, 3, 9}]=={} &]
Select[FromDigits/@Flatten[Table[Tuples[{2,3,9},n],{n,5}],1],PrimeQ] (* Harvey P. Dale, Apr 15 2025 *)
Table[(Prime[n]! + 3)/3, {n, 2, 30}]
a = {}; Do[k = 1; While[ ! PrimeQ[(k! + n)/n], k++ ]; AppendTo[a, k], {n, 1, 100}]; a
pr(n)=denominator(n)==1 && ispseudoprime(n) a(n)=my(k);until(pr(k++!/n+1),);k \\ Charles R Greathouse IV, Jul 15 2011
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