OFFSET
1,1
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
MATHEMATICA
f[n_] := f[n] = Prime[n] - n * DivisorSigma[0, n]; Select[Range[3500], f[#] == f[#+1] &] (* Amiram Eldar, Apr 08 2024 *)
PROG
(PARI) f(n) = prime(n) - n * numdiv(n);
is(n) = f(n) == f(n+1); \\ Amiram Eldar, Apr 08 2024
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Benoit Cloitre, Feb 24 2002
STATUS
approved