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A344628
Primes p such that exactly four numbers among all circular permutations of the digits of p are prime.
7
1193, 1931, 3119, 3779, 7793, 7937, 9311, 9377, 11393, 11701, 11717, 11743, 13177, 13931, 13997, 16993, 17011, 17117, 17431, 17539, 17713, 19717, 19997, 21737, 23339, 23773, 30197, 31139, 31699, 31771, 32377, 33923, 37217, 38197, 39233, 39499, 39799, 39971
OFFSET
1,1
LINKS
MATHEMATICA
Select[Prime[Range[4500]], Count[FromDigits/@Table[RotateRight[IntegerDigits[#], d], {d, IntegerLength[ #]}], _?PrimeQ]==4&] (* Harvey P. Dale, Aug 31 2024 *)
PROG
(PARI) rot(n) = if(#Str(n)==1, v=vector(1), v=vector(#n-1)); for(i=2, #n, v[i-1]=n[i]); u=vector(#n); for(i=1, #n, u[i]=n[i]); v=concat(v, u[1]); v
eva(n) = subst(Pol(n), x, 10)
is(n) = my(r=rot(digits(n)), i=0); while(r!=digits(n), if(ispseudoprime(eva(r)), i++); r=rot(r)); if(ispseudoprime(eva(r)), i++); if(n==1 || n==11, return(0)); if(i==4, 1, 0)
forprime(p=1, 1e3, if(is(p), print1(p, ", ")))
CROSSREFS
Cf. A270083. Row 4 of A317716.
Cf. primes where exactly k numbers among all circular permutations of digits are prime: A068654 (k=1), A344626 (k=2), A344627 (k=3), A344629 (k=5), A344630 (k=6), A344631 (k=7), A344632 (k=8).
Sequence in context: A040104 A103171 A032530 * A353263 A287049 A153379
KEYWORD
nonn,base
AUTHOR
Felix Fröhlich, May 25 2021
STATUS
approved