cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A112716 Smallest prime of the form: n successive positive integers in descending order followed by a 7.

This page as a plain text file.
%I A112716 #11 Dec 05 2013 19:57:06
%S A112716 17,547,3217,65437,543217,8765437,76543217,41403938373635347,
%T A112716 9876543217,282726252423222120197,1312111098765437,
%U A112716 2322212019181716151413127,222120191817161514131211107,1615141312111098765437
%N A112716 Smallest prime of the form: n successive positive integers in descending order followed by a 7.
%e A112716 a(4) = 65437, four successive positive integers 6,5,4,3 in descending order followed by a 7.
%t A112716 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 A112716 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 A112716 Cf. A114754, A114755, A114756, A114757, A114758, A114759, A108145.
%K A112716 base,nonn
%O A112716 1,1
%A A112716 _Amarnath Murthy_, Jan 01 2006
%E A112716 Extended by _Robert G. Wilson v_, _Ray Chandler_ and _Farideh Firoozbakht_, Jan 02 2006