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%I #12 Oct 15 2013 22:31:25
%S 0,0,1,2,3,6,7,10,11,14,19,20,25,28,29,32,37,42,43,48,51,52,57,60,65,
%T 72,75,76,79,80,83,96,99,104,105,114,115,120,125,128,133,138,139,148,
%U 149,152,153,164,175,178,179,182,187,188,197,202,207,212,213,218,221
%N a(1) = a(2) = 0; for n>2, a(n) = prime(n-1)-n+1.
%C Smallest x such that A002808(x)-x (cf. A073169) equals n, or 0 if no such value exists.
%F a(n)=Min{x; composite[x]-x=n}
%t f[x_] := FixedPoint[x+PrimePi[ # ]+1&, x] t=Table[0, {100}]; Do[s=f[n]-n; If[s<101&&t[[s]]==0, t[[s]]=n], {n, 1, 10000}]; t
%t Join[{0,0},Table[Prime[n-1]-n+1,{n,3,70}]] (* _Harvey P. Dale_, Dec 18 2012 *)
%Y Cf. A002808, A073168, A073169. Essentially same sequence as A014689.
%Y Cf. A000040, A014689.
%K nonn
%O 1,4
%A _Labos Elemer_, Jul 19 2002
%E Simpler description from _Vladeta Jovovic_, Mar 29 2003
%E Definition corrected by _Harvey P. Dale_, Dec 18 2012
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