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A344630 Primes p such that exactly six numbers among all circular permutations of the digits of p are prime. 7
193939, 199933, 319993, 331999, 391939, 393919, 919393, 933199, 939193, 939391, 993319, 999331, 1313999, 1317727, 1399913, 1731893, 1743737, 1772713, 1893173, 1977779, 2713177, 3139991, 3173189, 3177271, 3189317, 3717437, 4373717, 7174373, 7271317, 7318931 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Felix Fröhlich, Table of n, a(n) for n = 1..10000

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==6, 1, 0)

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

CROSSREFS

Cf. A270083. Row 6 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), A344629 (k=5), A344631 (k=7), A344632 (k=8).

Sequence in context: A258508 A254995 A232202 * A131907 A202937 A013901

Adjacent sequences:  A344627 A344628 A344629 * A344631 A344632 A344633

KEYWORD

nonn,base

AUTHOR

Felix Fröhlich, May 25 2021

STATUS

approved

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Last modified October 20 03:04 EDT 2021. Contains 348099 sequences. (Running on oeis4.)