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%I #14 Dec 25 2022 12:55:34
%S 4,74,94,116,270,464,556,654,1140,1156,1246,1306,1736,2464,2470,2604,
%T 2804,2836,2900,3054,3890,4006,4056,4330,4736,4780,5016,5294,5340,
%U 5486,5700,5834,6434,7114,7304,8626,8880,9164,9546,9744,9980,10086,10166
%N Positive integers n such that n^14 + 1 is semiprime (A001358).
%C x^14+1 has factors (1 + x^2) (1 - x^2 + x^4 - x^6 + x^8 - x^10 + x^12).
%H Robert Price, <a href="/A104335/b104335.txt">Table of n, a(n) for n = 1..1114</a>
%e 4^14 + 1 = 268435457 = 17 * 15790321,
%e 74^14 + 1 = 147653612273582215982104577 = 5477 * 26958848324553992328301,
%e 1140^14 + 1 = 6261349103849104148619671961600000000000001 = 1299601 * 4817901112610027345792802530622860401.
%t Select[ Range[2, 10422, 2], PrimeQ[ #^2 + 1] && PrimeQ[ #^12 - #^10 + #^8 - #^6 + #^4 - #^2 + 1] &] (*_Robert G. Wilson v_, Apr 18 2005 *)
%t Select[Range[2,10200,2],PrimeOmega[#^14+1]==2&] (* _Harvey P. Dale_, Oct 16 2011 *)
%Y Cf. A001358, A085722, A096173, A186669, A104238, A103854, A105041, A105066, A105078, A105122, A105142, A105237, A104335, A104479, A104494, A104657, A105282.
%K easy,nonn
%O 1,1
%A _Jonathan Vos Post_, Apr 17 2005
%E More terms from _Robert G. Wilson v_, Apr 18 2005
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