OFFSET
1,2
COMMENTS
Primes of the form a(k)-1: 2, 7, 17, 23, 47, 79, 109, 167, 197, 223, 239, 359, 439, 487, 701, 727, 839, 1087, 1223, 1297, 1367, ...
Numbers that occur in more than one way include 4^n - 4*n = 2^(2*n) - 2*(2*n). Are those all? - Robert Israel, Jul 21 2024
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
EXAMPLE
0 is in this sequence because 2^2 - 2*2 = 0 for x = 2 > 1 and y = 2 > 1.
MAPLE
N:= 10000: # for terms <= N
R:= {}:
for y from 2 while 2^y - 2*y <= N do
for x from 2 do
v:= x^y - x*y;
if v > N then break fi;
R:= R union {v};
od od:
sort(convert(R, list)); # Robert Israel, Jul 21 2024
CROSSREFS
KEYWORD
nonn
AUTHOR
Juri-Stepan Gerasimov, Sep 13 2014
STATUS
approved