A114754 Smallest prime of the form: n successive positive integers in ascending order followed by a 1.

11, 10111, 1231, 67891, 9101112131, 3456781, 91011121314151, 45678910111, 1234567891, 303132333435363738391, 12345678910111, 939495969798991001011021031041, 91011121314151617181920211

Offset: 1

Author

Amarnath Murthy, Jan 01 2006

Keywords

• base
• nonn

Examples

			a(2) = 10111= 10 followed by 11 followed by 1.
a(3) = 1231, three successive positive integers 1,2,3 in ascending order followed by a 1.
		

Crossrefs

Cf. A113513, A114755, A114756, A114757, A114758, A114759, A112716, A108145.

Programs

Mathematica

a[n_]:=(For[m=1, (v={};Do[v=Join[v, IntegerDigits[k]], {k, m, m+n-1}]);!PrimeQ[10FromDigits[v]+1], m++ ];10FromDigits[v]+1);Table[a[n], {n, 14}] - Farideh Firoozbakht
f[n_] := Block[{t = Range@n}, While[p = FromDigits@Flatten@IntegerDigits@Join[t, {1}]; !PrimeQ@p, t++ ]; p]; Array[f, 13] (* Robert G. Wilson v *)

Extensions

Extended by Robert G. Wilson v, Ray Chandler and Farideh Firoozbakht, Jan 02 2006