%I #2 Mar 30 2012 17:30:50
%S 2,5,13,23,37,53,71,97,131,157,191,223,263,307,347,383,431,467,521,
%T 587,653,709,787,853,937,1009,1087,1153,1237,1327,1423,1511,1613,1709,
%U 1823,1931,2053,2161,2269,2377,2503,2617,2749,2879,3011,3137,3299,3449,3613
%N Primes arising from the rearrangement of the natural numbers such that sum of n (n>1) terms starting from the n-th term (included) is a prime (A073672).
%t a = {2, 1, 4}; f[n_] := Block[{k = 1, b = Take[a, {n, 2n - 3}]}, While[ Position[a, k] != {}, k++ ]; b = Append[b, k]; a = Append[a, k]; While[ Position[a, k] != {} || !PrimeQ[Plus @@ b + k], k++ ]; a = Append[a, k]]; Do[ f[n], {n, 3, 50}]; Table[ Plus @@ Take[a, {n, 2n - 1}], {n, 1, 50}]
%Y Cf. A073672.
%K nonn
%O 1,1
%A _Robert G. Wilson v_, Sep 18 2002
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