This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A064239 #13 Oct 16 2019 11:27:50 %S A064239 6,36,306,366,546,726,966,1296,2556,3066,3696,3876,4506,6036,6216, %T A064239 7686,9126,9276,9906,10596,10656,10836,11286,12516,13146,14196,14406, %U A064239 14736,16266,17106,18216,19416,19476,20406,22146,22806,23766 %N A064239 Values of m such that N=(am+1)(bm+1)(cm+1) is a 3-Carmichael number (A087788), where a,b,c = 1,2,5. %C A064239 am+1, bm+1, cm+1 are primes and am | (N-1), bm | (N-1), cm |(N-1). %D A064239 Harvey Dubner (harvey(AT)dubner.com), personal communication, Jun 27 2001. %H A064239 Amiram Eldar, <a href="/A064239/b064239.txt">Table of n, a(n) for n = 1..10000</a> %t A064239 CarmichaelNbrQ[n_] := ! PrimeQ@ n && Mod[n, CarmichaelLambda@ n] == 1; Select[ Range@ 23800, PrimeQ[# + 1] && PrimeQ[2# + 1] && PrimeQ[5# + 1] && %t A064239 CarmichaelNbrQ[(# + 1)(2# + 1)(5# + 1)] &] (* _Robert G. Wilson v_, Aug 23 2012 *) %Y A064239 Cf. A087788. %K A064239 nonn %O A064239 1,1 %A A064239 _N. J. A. Sloane_, Sep 23 2001 %E A064239 Offset corrected by _Amiram Eldar_, Oct 16 2019