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A068526 Numbers n such that prime(n+1)-prime(n) = tau(n) = A000005(n). 4
1, 2, 3, 5, 6, 7, 8, 13, 14, 17, 18, 22, 24, 27, 32, 38, 41, 43, 65, 76, 80, 83, 85, 89, 93, 95, 109, 113, 122, 128, 134, 135, 143, 155, 159, 164, 173, 180, 183, 186, 188, 213, 226, 235, 237, 243, 245, 246, 247, 248, 249, 254, 275, 277, 284, 287, 292, 301, 303 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

R. J. Mathar, Table of n, a(n) for n = 1..10159

EXAMPLE

1 has 1 divisor, prime(1) is 2, and 2+1=3 is prime(1+1), so 1 is in the sequence.

2 has 2 divisors, prime(2) is 3, and 3+2=5 is prime(2+1), so 2 is in the sequence.

MAPLE

with(numtheory): A068526:=n->`if`(ithprime(n+1)-ithprime(n)=tau(n), n, NULL): seq(A068526(n), n=1..500); # Wesley Ivan Hurt, Apr 10 2015

CROSSREFS

Sequence in context: A028229 A104452 A062877 * A287339 A039086 A280060

Adjacent sequences:  A068523 A068524 A068525 * A068527 A068528 A068529

KEYWORD

easy,nonn

AUTHOR

Benoit Cloitre, Mar 21 2002

STATUS

approved

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Last modified January 21 13:55 EST 2020. Contains 331113 sequences. (Running on oeis4.)