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A227323 Prime(k) such that each of the three preceding and also each of the three following primes are twin primes. 0
11, 1039, 2099, 4253, 9433, 9437, 62983, 62987, 72229, 72251, 91121, 386401, 392269, 392279, 495589, 495611, 626617, 663583, 663587, 754973, 873553, 908857, 909301, 909317, 909319, 909329, 972137, 1006309, 1006331, 1138393, 1138409, 1159201 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The union of sequences A069456 and A227063.

Prime(k) such that prime(k-i), i=1..3, and prime(k+i), i=1..3 are in A001097.

LINKS

Table of n, a(n) for n=1..32.

MAPLE

istwp := proc(n)

    if isprime(n) then

        if isprime(n+2) or isprime(n-2) then

            true;

        else

            false;

        end if;

    else

        false;

    end if;

end proc:

for i from 4 do

    p := ithprime(i) ;

    p1 := prevprime(p) ;

    if istwp(p1) then

        p2 := prevprime(p1) ;

        if istwp(p2) then

            p3 := prevprime(p2) ;

            if istwp(p3) then

                p1 := nextprime(p) ;

                if istwp(p1) then

                    p2 := nextprime(p1) ;

                    if istwp(p2) then

                        p3 := nextprime(p2) ;

                        if istwp(p3) then

                            printf("%d\n", p) ;

                        end if;

                    end if;

                end if;

            end if;

        end if;

    end if;

end do: # R. J. Mathar, Jul 13 2013

CROSSREFS

Sequence in context: A046187 A234634 A004811 * A126197 A090814 A347846

Adjacent sequences:  A227320 A227321 A227322 * A227324 A227325 A227326

KEYWORD

nonn

AUTHOR

Irina Gerasimova, Jul 06 2013

EXTENSIONS

Corrected by R. J. Mathar, Jul 13 2013

STATUS

approved

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Last modified December 4 04:49 EST 2021. Contains 349469 sequences. (Running on oeis4.)