OFFSET
1,1
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
EXAMPLE
2 = 2^2 - 2,
5 = 2^3 - 3,
7 = 3^2 - 2,
11 = 3^2 + 2,
23 = 5^2 - 2,
37 = 2^5 + 5,
47 = 7^2 - 2,
61 = 4^3 - 3,
67 = 4^3 + 3,
79 = 9^2 - 2,
83 = 9^2 + 2,
167 = 13^2 - 2,
223 = 15^2 - 2,
227 = 15^2 + 2,
359 = 19^2 - 2,
439 = 21^2 - 2,
443 = 21^2 + 2,
503 = 2^9 - 9,
509 = 8^3 - 3,
521 = 2^9 + 9,
...
MAPLE
N:= 10000: # for terms <= N
S:= {2}:
for m from 2 while m^2-2 <= N do
for k from 3-(m mod 2) by 2 do
v:= m^k-k;
if v > N then break fi;
if isprime(v) then S:= S union {v} fi;
v:= m^k + k;
if v <= N and isprime(v) then S:= S union {v} fi;
od od:
sort(convert(S, list)); # Robert Israel, Mar 02 2026
CROSSREFS
KEYWORD
nonn
AUTHOR
Luke Voyles, Jun 05 2021
STATUS
approved
