A337190 Numbers k such that A337183(k) and k + A337183(k) are prime.

6, 10, 22, 42, 68, 102, 106, 116, 126, 168, 170, 178, 186, 202, 230, 242, 262, 356, 366, 436, 480, 502, 506, 516, 610, 622, 630, 638, 668, 696, 716, 778, 788, 798, 868, 890, 990, 1018, 1034, 1042, 1070, 1108, 1126, 1166, 1186, 1198, 1206, 1228, 1264, 1268, 1350, 1388, 1446, 1614, 1650, 1682, 1690

Offset

1,1

Comments

All terms are even.

Links

Robert Israel, Table of n, a(n) for n = 1..10000

Example

a(3) = 22 is a member because A337183(22) = 37 and 37+22 = 59 are both prime.

Maple

f:= proc(n) local F, b, i;
  F:= sort(map(t -> t[1]$t[2], ifactors(n)[2]), `>`);
  b:= convert(F, `+`);
  (add(F[i]*b^(i-1), i=1..nops(F)));
end proc:
filter:= proc(n) local v;
  v:= f(n); isprime(v) and isprime(v+n)
end proc:
select(filter, 2*[$1..1000]);

Mathematica

Select[Range[2, 1690], AllTrue[If[PrimeQ@ #, #, FromDigits[#, Total[#]] &@ Flatten[ConstantArray @@@ FactorInteger[#]]] + {0, #}, PrimeQ] &] (* Michael De Vlieger, Jan 29 2021 *)

Crossrefs

Cf. A337183. Contained in A337185.

Sequence in context: A216049 A063765 A085712 * A179875 A166305 A047651

Adjacent sequences: A337187 A337188 A337189 * A337191 A337192 A337193

Keyword

nonn,base

Author

J. M. Bergot and Robert Israel, Jan 29 2021

Status

approved