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%I #8 Apr 14 2020 12:11:41
%S 5,593,647,1097,1187,1367,1453,1663,1753,1783,1873,1907,2287,2377,
%T 2417,2683,3463,3637,3923,4513,5413,5807,6263,6317,6373,7523,7823,
%U 8087,8117,8237,8713,10853,11807,11833,11903,15313,15803,16063,16223,17027,18223
%N Primes p such that p + d and p-d are primes, where d is the sum of floors of square roots of the digits of p.
%H Robert Israel, <a href="/A179634/b179634.txt">Table of n, a(n) for n = 1..2000</a>
%e a(3)=647 since 647+[int(sqrt(6))+int(sqrt(4))+int(sqrt(7))]=647+(2+2+2)=647+6=653 is prime AND 647-6=641 is prime.
%p filter:= proc(p) local L,t,d;
%p if not isprime(p) then return false fi;
%p L:= convert(p,base,10);
%p d:= add(floor(sqrt(t)),t=L);
%p isprime(p-d) and isprime(p+d)
%p end proc:
%p select(filter, [seq(i,i=3..20000,2)]); # _Robert Israel_, Apr 14 2020
%o (PARI) isok(p) = isprime(p) && (d=digits(p)) && (sd = sum(i=1, #d, sqrtint(d[i]))) && isprime(p+sd) && isprime(p-sd); \\ _Michel Marcus_, Jan 19 2014
%K nonn,base
%O 1,1
%A _Carmine Suriano_, Jul 21 2010
%E Definition clarified by _Robert Israel_, Apr 14 2020