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A268068 First occurrence of n in the decimal expansion of Mersenne prime 2^74207281 - 1. 1
2, 8, 18, 1, 7, 20, 6, 5, 9, 22, 167, 240, 196, 156, 51, 143, 31, 241, 8, 74, 18, 73, 138, 71, 154, 217, 96, 119, 160, 21, 1, 166, 72, 63, 64, 28, 87, 4, 172, 57, 210, 7, 81, 56, 103, 65, 12, 68, 52, 374, 35, 239, 20, 90, 67, 66, 38, 178, 42, 29, 13, 15, 174, 44, 6 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

The largest known prime as of Jan 07 2016 is 2^74207281 - 1. The number itself contains 22,338,618 digits; all integers with fewer than 7 digits are contained within M74207281. The first number not contained in M74207281 is 1000003, so this sequence stops at a(1000002) = 1505496.

LINKS

Michael P. Tilley, Table of n, a(n) for n = 0..9999

Michael P. Tilley, A larger file of the sequence for n= 0 - 1000002

Brady Haran and Matt Parker, More details about the World's Biggest Prime (2016)

EXAMPLE

The first few digits of M74207281 are 30037641808460618205298609835916605...

Starting with three as the first digit count the position of n from the beginning

0 is the second digit,

1 is the eighth digit,

2 18,

3 1,

4 7, etc.

CROSSREFS

Cf. A000043, A267875.

Sequence in context: A295147 A215933 A154349 * A073601 A051248 A228615

Adjacent sequences:  A268065 A268066 A268067 * A268069 A268070 A268071

KEYWORD

nonn,base,fini

AUTHOR

Michael P. Tilley, Jan 25 2016

STATUS

approved

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Last modified December 18 12:36 EST 2018. Contains 318229 sequences. (Running on oeis4.)