A096069 - OEIS

A096069

Smallest prime ending in prime(n) and == 1 (mod prime(n)), or 0 if no such prime exists.

0, 13, 0, 127, 2311, 313, 4217, 419, 21023, 929, 13331, 30637, 5741, 16943, 10247, 15053, 3659, 21961, 13267, 12071, 4673, 22279, 4483, 43789, 25997, 414101, 24103, 188107, 132109, 93113, 373127, 816131, 264137, 798139, 693149, 400151, 582157

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OFFSET

1,2

COMMENTS

a(1) = a(3) = 0. Conjecture: No other term is zero.

I checked all n's <1450 with each having the required prime form. - Robert G. Wilson v, Jun 22 2004

LINKS

Table of n, a(n) for n=1..37.

EXAMPLE

a(6) = 1613 is a prime and 1613 ==1 mod (13), prime(6) = 13.

MATHEMATICA

f[n_] := Block[{k = 1, l = Floor[ Log[10, Prime[n]] + 1], p = Prime[n]}, If[n == 1 || n == 3, 0, While[ !PrimeQ[k*10^l + p] || Mod[k*10^l + p, p] != 1, k++ ]; k*10^l + p]]; Table[ f[n], {n, 37}] (* Robert G. Wilson v, Jun 22 2004 *)

CROSSREFS

Sequence in context: A114783 A094902 A252056 * A180265 A165400 A181154

Adjacent sequences: A096066 A096067 A096068 * A096070 A096071 A096072

KEYWORD

base,nonn

AUTHOR

Amarnath Murthy, Jun 20 2004

EXTENSIONS

Edited, corrected and extended by Robert G. Wilson v, Jun 22 2004

STATUS

approved