OFFSET
1,1
COMMENTS
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
FORMULA
gcd(a(n), A104621(a(n))) > 1.
EXAMPLE
MATHEMATICA
m=300; s = LinearRecurrence[{1, 1, 1, 1, 1, 1, 1}, {7, 1, 3, 7, 15, 31, 63}, m+1]; Select[Range[m], !CoprimeQ[#, s[[#+1]]] &] (* Amiram Eldar, Sep 05 2019 *)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Jonathan Vos Post, Apr 26 2005
EXTENSIONS
Offset corrected and a(5)-a(6) and more terms added by Amiram Eldar, Sep 05 2019
STATUS
approved