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 A228139 #12 Jul 29 2017 10:13:59 %S A228139 23,29,41,43,47,83,89,127,149,181,223,227,229,241,251,263,271,277,293, %T A228139 347,349,367,383,389,419,431,433,439,457,479,487,541,587,631,641,643, %U A228139 647,653,659,673,677,743,761,853,857,859,863,883,887,1123,1229,1279,1297,1423,1459,1489,1523 %N A228139 Primes such that the product of their digits subtracted from the prime number is another prime. %H A228139 Paolo P. Lava, <a href="/A228139/b228139.txt">Table of n, a(n) for n = 1..1000</a> %e A228139 23 is a member since 23-(2*3)=17. 29 is a member since 29-(2*9)=11. %t A228139 pdsQ[n_]:=Module[{pr=Times@@IntegerDigits[n]},pr!=0&&PrimeQ[n-pr]]; Select[Prime[Range[300]],pdsQ] (* _Harvey P. Dale_, Jul 29 2017 *) %o A228139 (PARI) dprod(n)=my(v=digits(n));prod(i=1,#v,v[i]) %o A228139 is(n)=my(d=dprod(n)); d>0 && isprime(n) && isprime(n-d) \\ _Charles R Greathouse IV_, Aug 12 2013 %Y A228139 Subsequence of A038618. %K A228139 nonn,base %O A228139 1,1 %A A228139 _Will Gosnell_, Aug 12 2013 %E A228139 a(3), a(10), a(15)-a(57) from _Charles R Greathouse IV_, Aug 12 2013