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A027569 Initial members of prime decaplets (p, p+2, p+6, p+8, p+12, p+18, p+20, p+26, p+30, p+32). 33
11, 33081664151, 83122625471, 294920291201, 573459229151, 663903555851, 688697679401, 730121110331, 1044815397161, 1089869189021, 1108671297731, 1235039237891, 1291458592421, 1738278660731 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

All terms are congruent to 11 (modulo 210). - Matt C. Anderson, May 28 2015

LINKS

Matt C. Anderson and Dana Jacobsen, Table of n, a(n) for n = 1..10000 [first 100 terms by Matt C. Anderson]

T. Forbes, Prime k-tuplets

MAPLE

composite_small := proc (n::integer)

description "procedure to determine if n has a prime factor less than 100";

if igcd(2305567963945518424753102147331756070, n) = 1 then

return false else return true end if;

end proc;

# begin initialization section

p := [0, 2, 6, 8, 12, 18, 20, 26, 30, 32]; o := [1271, 1691]; m := 2310;

# end initialization section

with(ArrayTools); os := Size(o, 2); ps := Size(p, 2);

loopstop := 10^11; loopstart := 0;

print(11);

for n from loopstart to loopstop do

for a to os do

counter := 0; wc := 0; wd := 0;

while `and`(wd > -10, wd < ps) do

wd := wd+1;

if composite_small(m*n+o[a]+p[wd]) = false then wd := wd+1 else wd := -10 end if;

end do;

if wd >= 9 then while `and`(counter >= 0, wc < ps) do

wc := wc+1;

if isprime(m*n+o[a]+p[wc]) then counter := counter+1 else counter := -1 end if end do;

end if;

if counter = ps then print(m*n+o[a]); end if;

end do;

end do;

# Matt C. Anderson, Apr 30 2015

PROG

(PARI) is(n)=isprime(n) && isprime(n+2) && isprime(n+6) && isprime(n+8) && isprime(n+12) && isprime(n+18) && isprime(n+20) && isprime(n+26) && isprime(n+30) && isprime(n+32)

v=primes(10); t=1; forprime(p=31, 1e11, v[t]=p; t=(t%10)+1; if(p-v[t]==32 && is(v[t]), print1(v[t]", "))) \\ Charles R Greathouse IV, May 20 2015

(Perl) use ntheory ":all"; say for sieve_prime_cluster(1, 1e13, 2, 6, 8, 12, 18, 20, 26, 30, 32); # Dana Jacobsen, Sep 30 2015

CROSSREFS

Sequence in context: A275573 A247846 A257127 * A202282 A131680 A262595

Adjacent sequences:  A027566 A027567 A027568 * A027570 A027571 A027572

KEYWORD

nonn

AUTHOR

Warut Roonguthai

STATUS

approved

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Last modified December 9 00:45 EST 2016. Contains 278959 sequences.