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.
13 is a term since a nontrivial permutation of its digits yields 31, which is also a prime.
dmax:=3: # for all terms of up to dmax digits
Res:= {}:
p:= 1:
do
p:= nextprime(p);
if p > 10^dmax then break fi;
L:= sort(convert(p,base,10),`>`);
m:= add(L[i]*10^(i-1),i=1..nops(L));
if assigned(A[m]) then
if ilog10(A[m])=ilog10(p) then
Res:= Res union {A[m], p}
else Res:= Res union {p}
fi
else A[m]:= p
fi
od:
sort(convert(Res,list)); # Robert Israel, Aug 13 2019
t={}; Do[p = Prime[n]; list1 = Permutations[IntegerDigits[p]]; If[Length[ Select[Table[FromDigits[n], {n,list1}], PrimeQ]] > 1, AppendTo[t,p]], {n,84}]; t
is(p) = if(isprime(p), my(d=vecsort(digits(p))); d==vector(#d,x,1)&&return(1); forperm(d, e, my(c = fromdigits(Vec(e))); p!=c && isprime(c) && return(1))); \\ Ruud H.G. van Tol, Jan 22 2023
from sympy import isprime
from itertools import permutations
def ok(n):
if not isprime(n): return False
perms = (int("".join(p)) for p in permutations(str(n)))
return any(isprime(t) for t in perms if t != n)
print([k for k in range(500) if ok(k)]) # Michael S. Branicky, Sep 14 2022
From _Michael De Vlieger_, Jul 14 2015: (Start) 16 is a term because it is the result of sorting the digits of prime 61 in ascending order, and 61 contains no zeros. 49 is not a term since neither 49 nor 94 are prime, and the prime 409 contains a zero. 133 is a term because while 133 itself is composite, both 313 and 331 are prime and contain no zeros. (End)
Sort@ DeleteDuplicates[FromDigits@ Sort@ IntegerDigits@ # & /@ Select[Prime@ Range@ PrimePi[10^3], Last@ DigitCount@ # == 0 &]] (* Michael De Vlieger, Jul 14 2015 *)
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