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A118741 Primes for which the weight as defined in A117078 is 7. 1
67, 83, 167, 193, 251, 277, 433, 487, 503, 587, 601, 613, 727, 823, 907, 1063, 1217, 1231, 1553, 1663, 1777, 1861, 1873, 1973, 1987, 2083, 2281, 2293, 2351, 2377, 2393, 2797, 2897, 3217, 3343, 3541, 3847, 4073, 4283, 4451, 4507, 4591, 4813, 4871, 5081 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The gap as defined in A001223 of this prime numbers is 4 or 6.

The prime numbers in this sequence are of the form (14i-1) (if gap=6) or (14i-3) (if gap=4) with i=(level(n)+1)/2, level(n) defined in A117563.

LINKS

Remi Eismann, Table of n, a(n) for n=1..10000

FORMULA

A117078 : a(n) = smallest k such that prime(n+1) = prime(n) + (prime(n) mod k), or 0 if no such k exists. prime(n) for which k=7.

MATHEMATICA

f[n_] := Block[{a, p = Prime[n], np = Prime[n + 1]}, a = Min[Select[Divisors[2*p - np], #1 > np - p & ]]; If[a == Infinity, 0, a]]; Prime@ Select[ Range@695, f@# == 7 &] - Robert G. Wilson v, May 26 2006

CROSSREFS

Cf. A117078, A117563, A118922, A118924.

Sequence in context: A091490 A091075 A139973 * A217115 A130058 A207293

Adjacent sequences:  A118738 A118739 A118740 * A118742 A118743 A118744

KEYWORD

nonn

AUTHOR

Rémi Eismann, May 22 2006; May 27 2006; May 04 2007

EXTENSIONS

More terms from Robert G. Wilson v, May 26 2006

STATUS

approved

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Last modified May 26 09:12 EDT 2017. Contains 287093 sequences.