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%I #12 Jul 07 2023 18:42:42
%S 5,3,1,6,6,6,14,6,9,19,21,21,42,93,21,6,11,2,12,111,37,39,63,38,42,24,
%T 15,15,60,6,39,82,47,58,337,49,72,25,34,21,6,107,128,96,20,2,63,231,
%U 70,7,62,144,28,151,157,33,98,55,134,162,87,201,124,303,64,106,130,13,43
%N Smallest k such that k*10^n is a sum of two successive primes.
%C From _Robert G. Wilson v_, Aug 11 2010: (Start)
%C A179975 n's such that a(n)=1: 3, 335, ..., .
%C A179975 First occurrence of k: 3, 18, 2, ???, 1, 4, 50, 162, 9, 335, 17, 19, 68, 7, 27, ..., .
%C Records: 5, 6, 14, 19, 21, 42, 93, 111, 337, 449, 862, 1049, 1062, 1122, 1280, 2278, 3168, 4290, ..., . (End)
%H Robert G. Wilson v, <a href="/A179975/b179975.txt">Table of n, a(n) for n = 0..400</a>.
%H Dario Alejandro Alpern, <a href="https://www.alpertron.com.ar/BRILLIANT.HTM"> Brilliant numbers</a>
%e a(0)=5 because 5=2+3
%e a(1)=3 because 30=13+17
%e a(2)=1 because 100=47+53
%e a(3)=6 because 6000=2999+3001.
%t Join[{5,3},Reap[Do[Do[n=10^m k; If[n==PreviousPrime[n/2]+NextPrime[n/2],Sow[k];Break[]],{k,2000}],{m,2,50}]][[2,1]]]
%t f[n_] := Block[{k = 1, tn = 10^n}, While[h = k*tn/2; NextPrime[h, -1] + NextPrime@h != k*tn, k++ ]; k]; f[1] = 3; Array[f, 70, 0] (* _Robert G. Wilson v_, Aug 11 2010 *)
%Y Cf. A064397, A071220, A074924, A074925.
%Y Cf. A033873, A033874, A005235, A055211, A038804, A084475.
%K nonn
%O 0,1
%A _Zak Seidov_, Aug 04 2010
%E More terms from _Robert G. Wilson v_, Aug 11 2010
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