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 A110069 #18 Jan 29 2024 09:01:28
%S A110069 188217,216925,329319,22146969,236256594,269226639788
%N A110069 Numbers n such that n = (d_1 + d_2 + ... + d_k)*prime(d_1*d_2*...*d_k) where d_1 d_2 ... d_k is the decimal expansion of n.
%C A110069 There is no further term up to 660000000.
%C A110069 This sequence is finite since (d_1+d_2+...+d_k)*prime(d_1*d_2*...*d_k) <= 9k * prime(9^k) << 9^k * k^2 << n. The bound can be made effective using the results of Dusart or others; for example, a(n) < 10^150. These can be improved with more work, but completing the sequence seems hard. - _Charles R Greathouse IV_, May 07 2011
%C A110069 a(7) > 7*10^14, if it exists. - _Giovanni Resta_, Jun 01 2020
%C A110069 If it exists, a(7) > 10^18. - _Max Alekseyev_, Jan 28 2024
%e A110069 236256594 is in the sequence because 236256594 = (2 + 3 + 6 + 2 + 5 + 6 + 5 + 9 +4)*prime(2*3*6*2*5*6*5*9*4).
%t A110069 Do[h = IntegerDigits[m]; l = Length[h]; If[Min[h] > 0 && m == Sum[h[[k]], {k, l}]*(Prime[Product[h[[k]], {k, l}]]), Print[m]], {m, 655000000}]
%Y A110069 Cf. A009994, A097640.
%K A110069 nonn,base,fini,more
%O A110069 1,1
%A A110069 _Farideh Firoozbakht_, Jul 17 2005
%E A110069 a(6) from _Giovanni Resta_, Jun 01 2020