A089740 - OEIS

%I #16 Jan 01 2024 11:21:06

%S 3,5,7,13,31,37,43,67,73,79,97,103,113,127,139,157,163,173,181,191,

%T 199,223,227,229,233,251,257,271,281,283,313,337,349,353,359,367,383,

%U 409,419,433,449,457,463,467,479,491,523,541,547,563,569,587,601,619,631

%N Primes which are digital complements (A055120) of primes.

%H Robert Israel, <a href="/A089740/b089740.txt">Table of n, a(n) for n = 1..10000</a>

%p A055120:= proc(n) local L;

%p   L:= map(t -> -t mod 10, convert(n,base,10));

%p   add(L[i]*10^(i-1),i=1..nops(L))

%p end proc:

%p filter:= t -> isprime(t) and isprime(A055120(t)):

%p select(filter, [seq(i,i=3..1000,2)]); # _Robert Israel_, Jun 29 2018

%t b=Delete[Union[ Table[If[PrimeQ[a[[n]]]==True,a[[n]],0],{n,1,Dimensions[a][[1]]}]],1]

%Y Cf. A055120.

%K nonn,base

%O 1,1

%A _Roger L. Bagula_, Jan 08 2004

%E Edited by _Charles R Greathouse IV_, Oct 28 2009

%E Name clarified by _Robert Israel_, Jun 29 2018