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A119705 Primes p such that number of divisors of p+1 equals number of divisors of p+2. 0
13, 37, 43, 97, 103, 157, 229, 241, 331, 373, 433, 541, 547, 877, 907, 1021, 1129, 1201, 1373, 1381, 1433, 1489, 1543, 1597, 1613, 1621, 1741, 1831, 1951, 1987, 2017, 2053, 2161, 2377, 2503, 2539, 2557, 2633, 2677, 2713, 2857, 2953, 3061, 3067, 3109, 3169 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Primes p such that A008329(p)=A049234(p).

LINKS

Table of n, a(n) for n=1..46.

EXAMPLE

13 is OK because both 14 and 15 have 4 divisors: {1, 2, 7, 14} and {1, 3, 5, 15}.

PROG

(PARI) isok(n) = isprime(n) && (numdiv(n+1) == numdiv(n+2)); \\ Michel Marcus, Oct 10 2013

CROSSREFS

Cf. A008329, A049234.

Sequence in context: A185006 A285887 A063913 * A155560 A217734 A319969

Adjacent sequences:  A119702 A119703 A119704 * A119706 A119707 A119708

KEYWORD

nonn

AUTHOR

Zak Seidov, Jul 29 2006

STATUS

approved

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Last modified December 17 14:12 EST 2018. Contains 318201 sequences. (Running on oeis4.)