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A320705
Indices of primes followed by a gap (distance to next larger prime) of 14.
2
30, 62, 66, 137, 146, 150, 162, 223, 250, 283, 309, 350, 360, 382, 402, 410, 424, 434, 503, 514, 526, 532, 536, 570, 610, 649, 654, 666, 687, 704, 706, 747, 780, 790, 867, 906, 919, 929, 967, 978, 981, 992, 1011, 1023, 1038, 1042, 1057, 1072, 1133, 1154, 1160, 1177, 1184
OFFSET
1,1
COMMENTS
Indices of the primes listed in A031932.
FORMULA
a(n) = A000720(A031932(n)).
A320705 = { i > 0 | prime(i+1) = prime(i) + 14 }.
MATHEMATICA
Select[Range[1500], Prime[#] + 14 == Prime[# + 1] &] (* Vincenzo Librandi, Mar 19 2019 *)
Position[Differences[Prime[Range[1200]]], 14]//Flatten (* Harvey P. Dale, Nov 28 2024 *)
PROG
(PARI) A(N=100, g=14, 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
(Magma) [n: n in [1..1500] | NthPrime(n+1) - NthPrime(n) eq 14]; // Vincenzo Librandi, Mar 19 2019
CROSSREFS
Equals A000720 o A031932.
Row 7 of A174349.
Indices of 14's in A001223.
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: A042794 A042796 A042798 * A132771 A326158 A300790
KEYWORD
nonn,changed
AUTHOR
M. F. Hasler, Oct 19 2018
STATUS
approved