cp's OEIS Frontend

A212883 Numbers n such that n^4 - prime(n) is prime.

%I A212883 #24 Mar 26 2025 17:03:57
%S A212883 2,6,40,76,144,146,148,166,168,174,186,192,210,220,222,230,238,240,
%T A212883 258,290,338,364,372,378,384,398,400,402,442,446,482,492,532,536,554,
%U A212883 570,606,628,654,700,740,882,888,944,954,964,966,978,1038,1040,1072,1080
%N A212883 Numbers n such that n^4 - prime(n) is prime.
%C A212883 See A064712 for the sequence of values of n such that n^2-prime(n) is prime. - _John W. Layman_, May 29 2012
%C A212883 All terms are even. - _M. F. Hasler_, Jun 02 2012
%H A212883 Robert Israel, <a href="/A212883/b212883.txt">Table of n, a(n) for n = 1..10000</a>
%p A212883 A[1]:= 2: p:= 3: count:= 1:
%p A212883 for n from 4 to 10^4 by 2 do
%p A212883    p:= nextprime(nextprime(p));
%p A212883    if isprime(n^4-p) then
%p A212883      count:= count+1;
%p A212883      A[count]:= n;
%p A212883    fi
%p A212883 od:
%p A212883 seq(A[i],i=1..count); # _Robert Israel_, Jun 20 2017
%t A212883 Reap[Do[If[PrimeQ[n^4-Prime[n]],Sow[n]],{n,2,1200,2}]][[2,1]]
%t A212883 Select[Range[1200],PrimeQ[#^4-Prime[#]]&] (* _Harvey P. Dale_, Mar 26 2025 *)
%o A212883 (Magma) [n: n in [1..1200]|IsPrime(n^4-NthPrime(n))];
%o A212883 (PARI) for(n=1,999,isprime(n^4-prime(n))&print1(n","))  \\ _M. F. Hasler_, Jun 02 2012
%Y A212883 Cf. A064712, A212881.
%K A212883 nonn
%O A212883 1,1
%A A212883 _Zak Seidov_, May 29 2012