A216133 In the decimal expansion of Pi, the first occurrence of these primes begins at a prime position.

7, 19, 31, 41, 43, 79, 89, 107, 137, 157, 197, 233, 263, 271, 293, 317, 367, 379, 433, 449, 479, 491, 499, 601, 641, 653, 673, 751, 757, 761, 769, 787, 797, 821, 823, 827, 853, 887

Offset

1,1

Comments

We label the positions in 3.14159... so that 1 is in position 1, 4 in position 2, 1 in position 3, 5 in position 4, and so on.

Links

Table of n, a(n) for n=1..38.

Example

The first 19 in the decimal expansion of Pi (see A000796) starts in position 37, which is a prime.

Mathematica

pos_in_Pi={1, 6, 9, 2, 4, 7, 13, 11, 5, 49, 94, 148, 110, 1, 3, ....};
s={}; Do[If[PrimeQ[x]&&PrimeQ[pos_in_Pi[[x]]], AppendTo[s, pos_in_Pi]], {x, Length[v]}]; s

Crossrefs

Cf. A000796.

Sequence in context: A040045 A242476 A079021 * A079740 A030549 A017605

Adjacent sequences: A216130 A216131 A216132 * A216134 A216135 A216136

Keyword

nonn,base

Author

Vicente Izquierdo Gomez, Sep 01 2012

Extensions

Edited by N. J. A. Sloane, Sep 09 2012

Status

approved