A065989 The first n ternary digits of Pi expressed in decimal forms a prime.

2, 10, 14, 83, 669, 720, 921, 2944, 4567

Offset

1,1

Comments

No further terms up to 10000. - Harvey P. Dale, Oct 14 2018

Links

Table of n, a(n) for n=1..9.

Example

The first 10 ternary digits of Pi (A004602) are 1001021101 = 20611 in decimal, which is a prime.

Mathematica

Do[ If[ PrimeQ[ FromDigits[ First[ RealDigits[Pi, 2, n]], 2]], Print[n]], {n, 1, 5000} ]
Module[{nn=4600, pd}, pd=RealDigits[Pi, 3, nn][[1]]; Position[Table[ FromDigits[ Take[ pd, n], 3], {n, nn}], _?(PrimeQ[#]&)]]//Flatten (* Harvey P. Dale, Oct 14 2018 *)

Crossrefs

Cf. A004602.

Sequence in context: A047043 A244268 A233454 * A299378 A031222 A272041

Adjacent sequences: A065986 A065987 A065988 * A065990 A065991 A065992

Keyword

base,nonn

Author

Robert G. Wilson v, Dec 10 2001

Status

approved