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A114783 Smallest prime of the form: all ones followed by prime(n). a(n) >prime(n). 0 if no such prime exists. 4
0, 13, 0, 17, 1111111111111111111, 113, 1117, 11119, 1123, 1129, 131, 137, 11111141, 111143, 11111111111111111111111111111147, 1153, 11159, 11161, 167, 1171, 173, 179, 1111183, 1111189, 197, 11111101, 1103, 11111111111111107, 1109 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Prime(n) is all zeros followed by prime(n). This is all ones followed by prime(n). Conjecture: No term is zero except a(1) = a(3) = 0.

LINKS

Table of n, a(n) for n=1..29.

EXAMPLE

a(7) = 1117, as 117 is composite prime(8) = 17.

MATHEMATICA

spf[n_]:=Module[{x=IntegerLength[n]+1, idn=IntegerDigits[n]}, While[ !PrimeQ[ FromDigits[ PadLeft[ idn, x, 1]]], x++]; FromDigits[ PadLeft[ idn, x, 1]]]; Join[{0, 13, 0}, spf/@Prime[Range[4, 30]]] (* Harvey P. Dale, May 22 2014 *)

CROSSREFS

Cf. A114784.

Sequence in context: A073867 A114782 A065112 * A094902 A252056 A096069

Adjacent sequences:  A114780 A114781 A114782 * A114784 A114785 A114786

KEYWORD

base,nonn

AUTHOR

Amarnath Murthy, Nov 17 2005

EXTENSIONS

More terms from Joshua Zucker, May 06 2006

STATUS

approved

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Last modified May 22 22:13 EDT 2022. Contains 353959 sequences. (Running on oeis4.)