A337439 a(n) is the k-th prime, such that abs(prime(k) - Sum_{j=k-2..k+2} prime(j)) sets a new record. A337438 are the corresponding values of k.

5, 7, 19, 47, 97, 109, 113, 199, 887, 1151, 1277, 1327, 9551, 11777, 14143, 15727, 19609, 25471, 31397, 156007, 360653, 370261, 492113, 1357201, 1357333, 1562051, 2010733, 4652507, 17051887, 20831323, 47326693, 47326913, 122164747, 189695893, 428045741, 436273291, 1453168433

Offset

1,1

Links

Table of n, a(n) for n=1..37.

Example

List of first terms:
   a(n)  pi(a(n))  average-median
     5,      3,     3/5  = (2 + 3 + 5 + 7 + 11)/5 - 5
     7,      4,     4/5 = (3 + 5 + 7 + 11 + 13)/5 - 7
    19,      8,     6/5 = (13 + 17 + 19 + 23 + 29)/5 - 19
    47,     15,     8/5
    97,     25,   -12/5
   109,     29,    14/5
   113,     30,    22/5
   199,     46,    28/5
   887,    154,    34/5
  1151,    190,   -36/5
  1277,    206,   -38/5
  1327,    217,    12
  9551,   1183,    14

Prog

(PARI) a337439(limp) = {my(p1=0, p2=2, p3=3, p4=5, p5=7, s=p1+p2+p3+p4+p5, d=0); forprime(p=11, limp, s=s-p1+p; my(dd=abs(s/5-p4)); if(dd>d, print1(p4, ", "); d=dd); p1=p2; p2=p3; p3=p4; p4=p5; p5=p)};
a337439(500000000)

Crossrefs

Cf. A034964, A337438, A337488, A337489.

Sequence in context: A079361 A162268 A045447 * A159048 A290415 A288906

Adjacent sequences: A337436 A337437 A337438 * A337440 A337441 A337442

Keyword

nonn

Author

Hugo Pfoertner, Aug 29 2020

Status

approved