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%I #11 Dec 05 2013 19:57:06
%S 17,547,3217,65437,543217,8765437,76543217,41403938373635347,
%T 9876543217,282726252423222120197,1312111098765437,
%U 2322212019181716151413127,222120191817161514131211107,1615141312111098765437
%N Smallest prime of the form: n successive positive integers in descending order followed by a 7.
%e a(4) = 65437, four successive positive integers 6,5,4,3 in descending order followed by a 7.
%t a[n_]:=(For[m=1, (v={};Do[v=Join[v, IntegerDigits[k]], {k, m+n-1, m, -1}]);!PrimeQ[10FromDigits[v]+7], m++ ];10FromDigits[v]+7);Table[a[n], {n, 14}] - Farideh Firoozbakht
%t f[n_] := Block[{t = Reverse@Range@n}, While[p = FromDigits@Flatten@IntegerDigits@Join[t, {7}]; !PrimeQ@p, t++ ]; p]; Array[f, 14] (* _Robert G. Wilson v_ *)
%Y Cf. A114754, A114755, A114756, A114757, A114758, A114759, A108145.
%K base,nonn
%O 1,1
%A _Amarnath Murthy_, Jan 01 2006
%E Extended by _Robert G. Wilson v_, _Ray Chandler_ and _Farideh Firoozbakht_, Jan 02 2006
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