%I #6 Nov 26 2020 23:06:52
%S 1,4,12,66,346,5876,95078,9411222,1894078221
%N Indices in A338884 where records occur.
%C It seems that A338884(a(n)) = n and 3*sqrt(log(a(n)))/n ~ O(1).
%o (Python)
%o from sympy import isprime
%o def search(n):
%o k = 1
%o while 1:
%o i = k*n + 1
%o while i < k*n + k:
%o if isprime(i) == 1: return i
%o i += 2
%o k = 2*k
%o a_rec = 0
%o n = 1
%o while 1:
%o m = search(n)
%o a = m.bit_length() - n.bit_length()
%o if a > a_rec:
%o print(n)
%o a_rec = a
%o n += 1
%Y Cf. A000040, A070939, A208241, A338884.
%K nonn,base,more
%O 1,2
%A _Ya-Ping Lu_, Nov 24 2020