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%I #6 Jan 27 2019 20:30:13
%S 311,733,991,1511,1811,3433,3733,7717,7757,16111,79777,99989,112111,
%T 333323,334333,733333,778777,787777,911111,999199,1171111,3733333,
%U 9999299,11131111,11911111
%N The larger member of a near-repdigit emirp pair.
%C a(n) and an associated A173595 = A004086(a(n)) (not necessarily at the same position n) are a near-repdigit emirp pair, and all these pairs, sorted, generate A173594.
%p read("transforms") ; isA164937 := proc(n) local dse ; if isprime(n) and n > 100 then dse := convert(convert(n,base,10),multiset) ; if nops(dse) = 2 then op(2,op(1,dse)) = 1 and op(2,op(2,dse)) > 1 or op(2,op(1,dse)) > 1 and op(2,op(2,dse)) = 1; else false; end if ; else false; end if; end proc:
%p isA006567 := proc(n) if isprime(n) then pr := digrev(n) ; return isprime(pr) and pr <> n ; else false; end if; end proc:
%p isA173594 := proc(n) isA164937(n) and isA006567(n) ; end proc:
%p isA173596 := proc(n) return isA173594(n) and digrev(n) < n end proc:
%p for n from 2 do if isA173596(n) then printf("%d,",n) ; fi ; end do ; # _R. J. Mathar_, Mar 05 2010
%Y Cf. A173594, A173595.
%K base,nonn
%O 1,1
%A _Lekraj Beedassy_, Feb 22 2010
%E Keyword:base added by _R. J. Mathar_, Feb 24 2010, Mar 05 2010