A272304 Position of the first n-digit prime occurring in the decimal expansion of e.

1, 2, 1, 15, 25, 13, 1, 65, 20, 100, 38, 54, 8, 48, 40, 41, 9, 83, 152, 19, 52, 6, 16, 66, 4, 4, 69, 25, 28, 7, 97, 174, 4, 48, 127, 11, 40, 58, 48, 69, 45, 40, 34, 119, 6, 7, 92, 61, 2, 40, 138, 105, 332, 28, 70, 322, 62, 231, 78, 339, 245, 66, 49, 439, 298

Offset

1,2

Comments

Leading zeros are not allowed.

Links

Harvey P. Dale, Table of n, a(n) for n = 1..200

Example

a(1) = 1 because the initial digit "2" of e is prime.

Mathematica

With[{ed = RealDigits[E, 10, 10000][[1]]}, Table[Position[Partition[ed, n, 1], _?(PrimeQ[FromDigits[#]] && #[[1]] != 0 &), {1}, 1, Heads -> False], {n, 100}]] // Flatten

Crossrefs

Cf. A001113, A198344.

Sequence in context: A141510 A219899 A326600 * A266521 A039652 A374264

Adjacent sequences: A272301 A272302 A272303 * A272305 A272306 A272307

Keyword

nonn,base

Author

Harvey P. Dale, Apr 25 2016

Status

approved