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A087984 9-ish numbers (A011539) which are not lunar primes (A087097).

%I A087984 #27 Nov 21 2018 00:35:05
%S A087984 9,119,129,139,149,159,169,179,189,190,191,192,193,194,195,196,197,
%T A087984 198,199,229,239,249,259,269,279,289,290,291,292,293,294,295,296,297,
%U A087984 298,299,339,349,359,369,379,389,390,391,392,393,394,395,396
%N A087984 9-ish numbers (A011539) which are not lunar primes (A087097).
%C A087984 Three and four digit 9ish numbers are lunar primes iff the smallest digit is strictly smaller than the first and the last digit. This is no longer true from 10109 = 109 x 109 on (where x = lunar product).
%H A087984 M. F. Hasler, <a href="/A087984/b087984.txt">Table of n, a(n) for n = 1..10000</a>
%H A087984 D. Applegate, <a href="/A087061/a087061.txt">C program for lunar arithmetic and number theory</a>
%H A087984 D. Applegate, M. LeBrun and N. J. A. Sloane, <a href="http://arxiv.org/abs/1107.1130">Dismal Arithmetic</a>, preprint, arxiv:1107.1130, July 2011. [Note: we have now changed the name from "dismal arithmetic" to "lunar arithmetic" - the old name was too depressing.]
%H A087984 D. Applegate, M. LeBrun, N. J. A. Sloane, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL14/Sloane/carry2.html">Dismal Arithmetic</a>, J. Int. Seq. 14 (2011) # 11.9.8.
%H A087984 <a href="/index/Di#dismal">Index entries for sequences related to dismal (or lunar) arithmetic</a>
%F A087984 A011539 \ A087097. - _M. F. Hasler_, Nov 19 2018
%o A087984 From _M. F. Hasler_, Nov 19 2018: (Start)
%o A087984 (PARI) A087984=setminus(A011539, A087097)
%o A087984 A087984=[9]; for(L=3,4,forvec(d=vector(L,i,[i==1,9]),vecmax(d)==9&&vecmin(d)>=min(d[1],d[L])&&A087984=concat(A087984,fromdigits(d)))) \\ terms with < 5 digits
%o A087984 (PARI) is_A087984(n)=vecmax(digits(n))=9&&!is_A087097(n) \\ (End)
%Y A087984 Cf. A011539, A087097. A133626 and A134211 are subsequences.
%K A087984 nonn,base
%O A087984 1,1
%A A087984 _David Applegate_ and _N. J. A. Sloane_, Oct 30 2003