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A089782
Smallest prime of the form prime(k) concatenated with prime(k+n).
4
23, 37, 311, 211, 317, 523, 3767, 223, 229, 337, 1153, 241, 347, 353, 359, 1783, 367, 47137, 271, 379, 383, 283, 397, 53173, 5107, 17137, 3109, 41179, 2113, 11149, 2131, 2137, 29191, 19181, 11173, 3163, 3167, 5179, 19211, 2179, 3191, 5197, 7211, 13229
OFFSET
1,1
EXAMPLE
a(4) = 211 = prime(1) followed by prime(1+4).
MATHEMATICA
c[r_, s_] := ToExpression[ToString[r] <> ToString[s]]; Do[k = 1; While[ !PrimeQ[c[Prime[k], Prime[n + k]]], k++ ]; Print[c[Prime[k], Prime[n + k]]], {n, 1, 100}] (* Ryan Propper, Sep 02 2005 *)
CROSSREFS
Cf. A089783.
Sequence in context: A133957 A133980 A090312 * A113893 A146390 A233385
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Nov 24 2003
EXTENSIONS
Corrected and extended by Ryan Propper, Sep 02 2005
STATUS
approved