OFFSET
1,2
COMMENTS
No other terms below 10^15. - Max Alekseyev, Oct 14 2016
492385451091805616444 is a term.
EXAMPLE
3^25 + 7 = 847288609450 = 25 * 33891544378, so 25 is a term.
PROG
(PARI) is(n)=Mod(3, n)^n==-7; \\ Joerg Arndt, Oct 09 2016
(Python) A277289_list = [1, 2, 4, 5]+[n for n in range(6, 10**6) if pow(3, n, n)==n-7] # Chai Wah Wu, Oct 12 2016
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Oct 09 2016
EXTENSIONS
a(17) from Joerg Arndt, Oct 09 2016
a(18)-a(20) from Chai Wah Wu, Oct 12 2016
a(21)-a(26) from Max Alekseyev, Oct 14 2016
STATUS
approved