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A352852
Primes p such that, if q is the next prime, p^2 + q is a prime times a power of 10.
3
2, 523, 701, 2213, 2243, 3041, 3701, 4177, 4423, 6451, 7673, 8447, 8513, 9587, 11131, 15233, 15331, 15583, 17519, 19051, 20071, 20333, 22483, 24767, 25951, 26633, 28183, 28771, 28901, 30773, 33461, 33713, 38803, 39419, 39989, 41627, 42131, 43237, 44633, 50321, 50333, 51991, 53551, 54713, 56687
OFFSET
1,1
COMMENTS
Primes prime(k) such that when any trailing zeros are removed from A352851(k), the result is prime.
LINKS
EXAMPLE
a(3) = 701 is a term because it is prime, 709 is the next prime, and 701^2 + 709 = 492110 where 49211 is prime.
MAPLE
R:= NULL: count:= 0:
q:= 2:
while count < 100 do
p:= q; q:= nextprime(p);
v:= p^2+q;
if v mod 10 = 0 then v:= v/10^min(padic:-ordp(v, 2), padic:-ordp(v, 5)) fi;
if isprime(v) then count:= count+1; R:= R, p; fi;
od:
R;
MATHEMATICA
f[n_] := n/10^IntegerExponent[n, 10]; Select[Range[60000], PrimeQ[#] && PrimeQ[f[#^2 + NextPrime[#]]] &] (* Amiram Eldar, Apr 07 2022 *)
CROSSREFS
Sequence in context: A218436 A080778 A007513 * A283756 A352803 A071613
KEYWORD
nonn
AUTHOR
J. M. Bergot and Robert Israel, Apr 05 2022
STATUS
approved