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A320712
Indices of primes followed by a gap (distance to next larger prime) of 28.
1
429, 462, 685, 781, 1116, 1231, 1274, 1288, 1327, 1392, 1585, 1708, 1710, 1891, 1944, 2065, 2154, 2367, 2417, 2606, 2663, 2729, 2980, 3012, 3069, 3227, 3519, 3653, 3990, 4018, 4168, 4196, 4595, 4603, 4618, 4797, 4856, 4867, 5123, 5191, 5294, 5375, 5432, 5476, 5498, 5593, 5627, 5688, 5703
OFFSET
1,1
COMMENTS
Indices of the primes listed in A124595.
FORMULA
a(n) = A000720(A124595(n)).
A320712 = { i > 0 | prime(i+1) = prime(i) + 28 }.
PROG
(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
CROSSREFS
Equals A000720 o A124595.
Indices of 28's in A001223.
Row 14 of A174349.
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).
Sequence in context: A177328 A243833 A334558 * A338344 A203612 A250330
KEYWORD
nonn
AUTHOR
M. F. Hasler, Oct 19 2018
STATUS
approved