A138862 First two (i.e., the two most significant) digits of n-th Mersenne prime A000668(n).

3, 7, 31, 12, 81, 13, 52, 21, 23, 61, 16, 17, 68, 53, 10, 14, 44, 25, 19, 28, 47, 34, 28, 43, 44, 40, 85, 53, 52, 51, 74, 17, 12, 41, 81, 62, 12, 43, 92, 12, 29, 12, 31, 12, 20, 16, 31

Offset

1,1

Links

Table of n, a(n) for n=1..47.

L. C. Noll, Mersenne Prime Digits and Names.

Mathematica

Join[{3, 7}, FromDigits[Take[IntegerDigits[#], 2]]&/@ (2^MersennePrimeExponent[ Range[ 3, 47]]-1)] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Aug 01 2020 *)

Crossrefs

Cf. A000668, A080173, A138863, A138864, A138865, A138866.

Sequence in context: A354518 A009128 A053648 * A080173 A023266 A359702

Adjacent sequences: A138859 A138860 A138861 * A138863 A138864 A138865

Keyword

base,nonn

Author

Omar E. Pol, Apr 02 2008

Extensions

a(40)-a(47) from Ivan Panchenko, Aug 03 2018

Definition clarified by Harvey P. Dale, Aug 01 2020

Status

approved