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A181981 Smallest prime p such that n primes exist between the twin prime pair (p, p+2) and the next twin prime pair. 3
3, 17, 41, 107, 71, 2267, 1091, 461, 1319, 1151, 347, 5741, 2999, 5279, 10139, 1487, 9461, 881, 659, 13007, 9041, 15359, 8627, 28751, 83717, 13397, 18539, 14627, 44771, 54011, 60257, 59669, 142157, 77711, 61559, 178931, 26261, 122867, 293261, 89069, 24419 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Table of n, a(n) for n=0..40.

EXAMPLE

a(4)= 71 because the 4 primes 79, 83, 89, 97 exist between (71, 73) and (101,103).

MAPLE

A181981 := proc(n)

    local j, hi, lo ;

    if n = 0 then

        3;

    else

        for j from 1 do

                hi := numtheory[pi](A001359(j+1)) ;

                lo := numtheory[pi](A006512(j)) ;

                if hi-lo = n+1 then

                    return A001359(j);

                end if;

        end do:

    end if;

end proc: # R. J. Mathar, Jul 03 2012

CROSSREFS

Cf. A001359, A006512, A027833.

Sequence in context: A049078 A209544 A146821 * A089637 A135471 A322755

Adjacent sequences:  A181978 A181979 A181980 * A181982 A181983 A181984

KEYWORD

nonn

AUTHOR

Michel Lagneau, Jul 03 2012

STATUS

approved

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Last modified February 26 14:18 EST 2021. Contains 341632 sequences. (Running on oeis4.)