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A062969
Numbers k such that abs(d(k)-k-1) is prime, where d(k) is the number of divisors of k.
1
3, 4, 6, 8, 9, 10, 12, 14, 18, 22, 24, 25, 26, 28, 30, 34, 46, 49, 52, 54, 62, 66, 72, 74, 76, 78, 80, 82, 84, 86, 90, 104, 106, 108, 110, 112, 114, 134, 138, 142, 150, 160, 166, 169, 170, 172, 174, 176, 180, 186, 192, 194, 202, 204, 208, 214, 226, 230, 234, 244, 246
OFFSET
1,1
EXAMPLE
d(300)-300-1 = -283, absolute value of which is prime.
PROG
(PARI) j=[]; for(n=1, 300, if(isprime(numdiv(n)-n-1), j=concat(j, n))); j
CROSSREFS
Cf. A062968.
Sequence in context: A182829 A112800 A294456 * A175035 A025063 A050849
KEYWORD
easy,nonn
AUTHOR
Jason Earls, Jul 23 2001
STATUS
approved