OFFSET
1,5
LINKS
Clark Kimberling, Table of n, a(n) for n = 1..10000
EXAMPLE
prime(6) - 1 = 12 has divisors 1,2,3,4,6,12, so that k=6 and d(k+1-i) - d(i) ranges through {-11, -4, -1, 1, 4, 11}, so that a(6) = 1.
MATHEMATICA
f[n_] := f[n] = Prime[n]-1;
Table[Divisors[f[n]] - Reverse[Divisors[f[n]]], {n, 1, 10}]
Table[Min[Abs[Divisors[f[n]] - Reverse[Divisors[f[n]]]]], {n, 1, 100}]
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Apr 11 2017
STATUS
approved