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Smallest number m such that prime(n) = m + (digit sum of m), a(n)=0 if no such m exists.
3

%I #6 Sep 28 2014 00:13:45

%S 1,0,0,0,10,11,13,14,16,19,0,32,34,35,37,0,52,53,56,58,59,71,73,76,0,

%T 91,92,94,95,97,122,124,127,128,142,143,146,149,160,163,166,167,181,

%U 182,184,185,0,215,217,218,0,232,233,238,250,253,256,257,0,271

%N Smallest number m such that prime(n) = m + (digit sum of m), a(n)=0 if no such m exists.

%C If a(n)>0 then: A000040(n)=A062028(a(n)) and A107740(n)>0.

%H Reinhard Zumkeller, <a href="/A107741/b107741.txt">Table of n, a(n) for n = 1..10000</a>

%o (Haskell)

%o a107741 n = if null ms then 0 else head ms where

%o ms = [m | let p = a000040 n,

%o m <- [max 0 (p - 9 * a055642 p) .. p - 1], a062028 m == p]

%o -- _Reinhard Zumkeller_, Sep 27 2014

%Y Cf. A047791, A048521.

%Y Cf. A000040, A055642, A062028.

%K nonn,base

%O 1,5

%A _Reinhard Zumkeller_, May 23 2005

%E Data error corrected by _Reinhard Zumkeller_, Sep 27 2014