A064337 Minimal prime numbers with increasing prime differences.
2, 5, 11, 17, 29, 41, 59, 79, 101, 127, 157, 191, 229, 271, 317, 367, 421, 487, 557, 631, 709, 787, 877, 967, 1061, 1163, 1277, 1381, 1489, 1601, 1721, 1861, 1993, 2131, 2273, 2423, 2579, 2741, 2909, 3079, 3253, 3433, 3617, 3821, 4019, 4217, 4421, 4637
Offset: 1
Examples
a(5) = 29, since a(4) = 17, p(4) = 7 and 29 is the smallest prime which is not smaller than 17 + 7.
Links
- Harry J. Smith, Table of n, a(n) for n = 1..1000
Crossrefs
Cf. A064336.
Programs
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Mathematica
NextPrime[n_] := (k = n; While[ ! PrimeQ[k], k++ ]; k); f[1] = 2; f[n_] := NextPrime[ f[n - 1] + Prime[n-1] ]; Table[ f[n], {n, 1, 50} ] Transpose[NestList[{First[#]+1,NextPrime[Last[#]+Prime[First[#]]]}&, {1,2}, 50]][[2]] (* Harvey P. Dale, Oct 23 2011 *)
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PARI
for (n=1, 1000, if (n>1, a=nextprime(a + prime(n - 1)), a=2); write("b064337.txt", n, " ", a) ) \\ Harry J. Smith, Sep 12 2009
Formula
a(1) = 2, a(n+1) = MIN {prime p | p >= a(n) + prime(n)} (where prime(n) is the n-th prime number).
Conjecture: a(n) ~ K*n^2*log(n). - Bill McEachen, Apr 04 2024
a(n) >= A007504(n) >> n^2 log n. On Cramér's conjecture, a(n) << n^2 log^2 n. - Charles R Greathouse IV, Apr 10 2024