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.

A344629 Primes p such that exactly five numbers among all circular permutations of the digits of p are prime.

Original entry on oeis.org

11939, 19391, 19937, 37199, 39119, 71993, 91193, 93719, 93911, 99371, 103391, 103997, 107119, 110339, 111893, 111919, 113123, 113177, 113983, 114997, 117133, 117319, 117353, 117701, 118931, 119107, 119179, 119191, 119699, 123113, 127733, 129919, 131231, 131771
Offset: 1

Views

Author

Felix Fröhlich, May 25 2021

Keywords

Crossrefs

Cf. A270083. Row 5 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), A344628 (k=4), A344630 (k=6), A344631 (k=7), A344632 (k=8).

Programs

  • 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==5, 1, 0)
    forprime(p=1, 1e3, if(is(p), print1(p, ", ")))