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A084445
Primes that cannot be written as 1+p+p^k, p prime and k>0.
2
2, 3, 17, 29, 37, 41, 43, 53, 61, 71, 73, 79, 89, 97, 101, 103, 109, 113, 127, 137, 139, 149, 151, 157, 163, 173, 181, 191, 193, 197, 199, 211, 223, 229, 233, 239, 241, 251, 257, 269, 271, 277, 281, 283, 293, 311, 313, 317, 331, 337, 349, 353, 367, 373, 379
OFFSET
1,1
COMMENTS
A084440(a(n))=0.
LINKS
MAPLE
N:= 1000: # for terms <= N
S:= select(isprime, {2, seq(i, i=3..N, 2)}):
for i from 1 do
p:= ithprime(i);
if 2*p+1 > N then break fi;
for k from 1 do
q:= 1+p+p^k;
if q > N then break fi;
S:= S minus {q};
od;
od:
sort(convert(S, list)); # Robert Israel, Dec 13 2023
CROSSREFS
Cf. A084441.
Sequence in context: A029876 A248716 A228201 * A215303 A215280 A219559
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, May 26 2003
STATUS
approved