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a(1) = 2, a(2) = 3; for n > 0, a(n+2) is the smallest prime chosen so that (a(n+2) - a(n+1))/(a(n+1) - a(n)) is an integer.
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%I #13 Jul 29 2017 12:14:10

%S 2,3,5,7,11,19,43,67,139,211,283,499,1579,2659,3739,8059,12379,16699,

%T 21019,25339,38299,103099,167899,232699,491899,1787899,9563899,

%U 17339899,25115899,40667899,71771899,196187899,818267899,4550747899,15748187899

%N a(1) = 2, a(2) = 3; for n > 0, a(n+2) is the smallest prime chosen so that (a(n+2) - a(n+1))/(a(n+1) - a(n)) is an integer.

%C Successive differences are multiples of the previous difference.

%e 43, 67 and 139 are three successive terms and (139-67)/(67-43) = 3.

%t a[0] = 2; a[1] = 3; a[n_] := a[n] = Block[{k = 1}, While[ !PrimeQ[ k( a[n - 1] - a[n - 2]) + a[n - 1]], k++ ]; k(a[n - 1] - a[n - 2]) + a[n - 1]]; Table[ a[n], {n, 0, 34}]

%K nonn

%O 1,1

%A _Amarnath Murthy_ and Meenakshi Srikanth (menakan_s(AT)yahoo.com), Jun 14 2003

%E Edited and extended by _Robert G. Wilson v_ and _Vladeta Jovovic_, Jun 17 2003