|
|
A270104
|
|
Numbers k such that 3^k + k*2^k is prime.
|
|
1
|
|
|
1, 2, 7, 8, 13, 43, 55, 59, 145, 149, 545, 2468, 4049, 4055, 15653, 22765, 99932
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,2
|
|
COMMENTS
|
|
|
LINKS
|
|
|
EXAMPLE
|
n = 2 is a term since 3^2 + 2*2^2 = 17 is prime.
|
|
MATHEMATICA
|
Select[Range[1000], PrimeQ[3^# + # * 2^#]&] (* Giovanni Resta, May 05 2016 *)
|
|
PROG
|
(MATLAB)
if isprime(3^n + n*2^n)
disp(n)
end
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn,more
|
|
AUTHOR
|
|
|
EXTENSIONS
|
|
|
STATUS
|
approved
|
|
|
|