A179912 Primes with four embedded primes.

137, 173, 317, 373, 379, 523, 673, 1123, 1153, 1171, 1193, 1223, 1231, 1277, 1279, 1283, 1297, 1307, 1327, 1531, 1579, 1597, 1613, 1637, 1759, 1783, 1823, 1913, 1931, 2053, 2153, 2333, 2339, 2341, 2351, 2393, 2399, 2411, 2467, 2503, 2539, 2543, 2557

Offset

1,1

Comments

A079066(a(n)) = 4.

Links

Table of n, a(n) for n=1..43.

Mathematica

f[n_] := Block[ {id = IntegerDigits@n}, len = Length@ id - 1; Count[ PrimeQ@ Union[ FromDigits@# & /@ Flatten[ Table[ Partition[ id, k, 1], {k, len}], 1]], True] + 1]; Select[ Prime@ Range@ 380, f@# == 5 &]

Prog

(Haskell)
import Data.List (elemIndices)
a179912 n = a179912_list !! (n-1)
a179912_list = map (a000040 . (+ 1)) $ elemIndices 4 a079066_list
-- Reinhard Zumkeller, Jul 19 2011

Crossrefs

Cf. A039996, A079397, A033274, A034844, A092621, A179909 - A179919, A033274.

Sequence in context: A139647 A114645 A057879 * A108382 A106280 A356980

Adjacent sequences: A179909 A179910 A179911 * A179913 A179914 A179915

Keyword

base,nonn

Author

Robert G. Wilson v, Aug 01 2010

Status

approved