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 A145339 a(n) = the minimum of d(p(n)-1) and d(p(n)+1), where d(m) is the number of divisors of m and p(n) is the n-th prime. 2
 1, 2, 3, 4, 4, 4, 5, 6, 4, 6, 6, 4, 8, 6, 4, 6, 4, 4, 6, 8, 4, 8, 4, 8, 6, 8, 8, 4, 8, 8, 8, 8, 8, 8, 6, 8, 4, 6, 4, 6, 4, 8, 8, 4, 9, 12, 6, 8, 4, 8, 8, 8, 6, 8, 8, 4, 6, 10, 4, 8, 6, 6, 12, 8, 4, 6, 6, 6, 4, 12, 8, 4, 8, 8, 12, 4, 6, 4, 8, 8, 8, 4, 8, 8, 8, 8, 14, 4, 12, 10, 4, 4, 8, 12, 8, 4, 6, 12, 6, 4, 6 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS MATHEMATICA Table[Min[DivisorSigma[0, Prime[n]-1], DivisorSigma[0, Prime[n]+1]], {n, 1, 100}] (* Stefan Steinerberger, Oct 11 2008 *) PROG (PARI) a(n) = my(p = prime(n)); min(numdiv(p-1), numdiv(p+1)); \\ Michel Marcus, Sep 28 2018 CROSSREFS Cf. A145340, A008328, A008329, A067889, A103664, A103665. Sequence in context: A003160 A060740 A307467 * A123273 A284359 A167991 Adjacent sequences:  A145336 A145337 A145338 * A145340 A145341 A145342 KEYWORD nonn AUTHOR Leroy Quet, Oct 08 2008 EXTENSIONS More terms from Stefan Steinerberger and Ray Chandler, Oct 11 2008 STATUS approved

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Last modified December 8 20:37 EST 2021. Contains 349596 sequences. (Running on oeis4.)