OFFSET
1,1
COMMENTS
The record gap values are 50, 168, 239, 260, 406, 510, ... (see the link for more values).
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..59
Amiram Eldar, Table of n, a(n), gap(n) for n = 1..59
EXAMPLE
The first 5 terms of A071395 are 20, 70, 88, 104 and 272. The differences between these terms are 50, 18, 16, and 168. The record gaps are 50 and 168, which occur after the terms 20 and 104.
MATHEMATICA
primAbQ[n_] := DivisorSigma[1, n] > 2 n && AllTrue[Most @ Rest @ Divisors[n], DivisorSigma[1, #] < 2*# &]; seq = {}; m = 20; dm = 0; Do[If[primAbQ[n], d = n - m; If[d > dm, dm = d; AppendTo[seq, m]]; m = n], {n, 21, 10^6}]; seq
CROSSREFS
KEYWORD
nonn
AUTHOR
Amiram Eldar, Apr 29 2020
STATUS
approved