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A247269 Primes p such that p + m^2 is prime for all m in {2,4,6,8,10,12,14,16,18}. 4
163, 409333, 1483087, 1867783, 222640867, 258001837, 371305267, 748576753, 828497443, 1235054137, 2059599067, 5767711867, 5929920613, 8965599883, 9055004953, 9170160343, 9655686727, 9670115977, 9671300983, 10646399437, 12253792783, 12627473917, 19635778453 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

All terms are == 1 mod 6, and == {7, 13} mod 30.

Subsequence of A246842.

LINKS

Zak Seidov, Table of n, a(n) for n = 1..1592

PROG

(PARI)

forprime(p=1, 10^12, c=0; for(i=1, 9, if(ispseudoprime(p+(2*i)^2), c++); if(!ispseudoprime(p+(2*i)^2), break)); if(c==9, print1(p, ", "))) \\ Derek Orr, Sep 11 2014

(PARI) is(n)=my(t=n%5); if(t!=2 && t!=3, return(0)); forstep(i=4, 18, 2, if(!isprime(n+i^2), return(0))); isprime(n) && isprime(n+4)

p=2; forprime(q=3, 1e12, if(q-p==4 && is(p), print1(p", ")); p=q) \\ Charles R Greathouse IV, Sep 11 2014

CROSSREFS

Cf. A049492, A092120, A246842.

Sequence in context: A138200 A146504 A306501 * A145741 A247273 A247275

Adjacent sequences:  A247266 A247267 A247268 * A247270 A247271 A247272

KEYWORD

nonn

AUTHOR

Zak Seidov, Sep 11 2014

STATUS

approved

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Last modified April 5 03:52 EDT 2020. Contains 333238 sequences. (Running on oeis4.)