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%I #6 Oct 24 2018 19:17:04
%S 429,462,685,781,1116,1231,1274,1288,1327,1392,1585,1708,1710,1891,
%T 1944,2065,2154,2367,2417,2606,2663,2729,2980,3012,3069,3227,3519,
%U 3653,3990,4018,4168,4196,4595,4603,4618,4797,4856,4867,5123,5191,5294,5375,5432,5476,5498,5593,5627,5688,5703
%N Indices of primes followed by a gap (distance to next larger prime) of 28.
%C Indices of the primes listed in A124595.
%H <a href="/index/Pri#gaps">Index entries for primes, gaps between</a>.
%F a(n) = A000720(A124595(n)).
%F A320712 = { i > 0 | prime(i+1) = prime(i) + 28 }.
%o (PARI) A(N=100,g=28,p=2,i=primepi(p)-1,L=List())={forprime(q=1+p,,i++; if(p+g==p=q, listput(L,i); N--||break));Vec(L)} \\ returns the list of first N terms of the sequence
%Y Equals A000720 o A124595.
%Y Indices of 28's in A001223.
%Y Row 14 of A174349.
%Y Cf. A029707, A029709, A320701, A320702, ..., A320720 (analog for gaps 2, 4, 6, 8, ..., 44), A116493 (gap 70), A116496 (gap 100), A116497 (gap 200), A116495 (gap 210).
%K nonn
%O 1,1
%A _M. F. Hasler_, Oct 19 2018