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A320718
Indices of primes followed by a gap (distance to next larger prime) of 40.
2
2191, 2344, 2524, 2788, 3562, 4058, 4677, 5030, 5349, 6076, 6145, 6256, 6320, 6442, 6454, 6902, 7232, 7488, 8119, 8152, 8245, 8366, 8553, 8567, 8591, 8746, 9260, 9361, 10536, 10735, 11095, 11407, 11534, 11781, 12227, 12312, 12663, 12815, 12940, 13015, 13333, 13676, 13873, 14065, 14123
OFFSET
1,1
COMMENTS
Indices of the primes listed in A126721.
FORMULA
a(n) = A000720(A126721(n)).
A320718 = { i > 0 | prime(i+1) = prime(i) + 40 } = A001223^(-1)({40}).
PROG
(PARI) A(N=100, g=40, 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 A126721.
Row 20 of A174349.
Subsequence of A107730 (prime(n+1) ends in same digit as prime(n)).
Indices of 40'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: A085442 A208549 A251316 * A134158 A227488 A225719
KEYWORD
nonn
AUTHOR
M. F. Hasler, Oct 19 2018
STATUS
approved