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A176024 Reverse concatenation of the first a(n) integers gives a prime. 1
82, 37765 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(2) found by Eric W. Weisstein, Apr 06 2010.

a(n) = indices n for which A000422(n) is prime. - Arkadiusz Wesolowski, Apr 29 2012

LINKS

Table of n, a(n) for n=1..2.

Eric Weisstein's World of Mathematics, Consecutive Number Sequences

Eric Weisstein's World of Mathematics, Integer Sequence Primes

EXAMPLE

a(1) is 82 since the 155-digit number 828180...54321 is prime.

a(2) is 37765 since the 177719-digit number 377653776437763...54321 is prime.

CROSSREFS

Sequence in context: A241129 A289330 A282157 * A204976 A204703 A206648

Adjacent sequences:  A176021 A176022 A176023 * A176025 A176026 A176027

KEYWORD

nonn,hard,more,base,bref

AUTHOR

Eric W. Weisstein, Apr 06 2010

STATUS

approved

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Last modified December 5 09:47 EST 2020. Contains 338945 sequences. (Running on oeis4.)