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 A092517 Product of tau-values for consecutive integers. 11
 2, 4, 6, 6, 8, 8, 8, 12, 12, 8, 12, 12, 8, 16, 20, 10, 12, 12, 12, 24, 16, 8, 16, 24, 12, 16, 24, 12, 16, 16, 12, 24, 16, 16, 36, 18, 8, 16, 32, 16, 16, 16, 12, 36, 24, 8, 20, 30, 18, 24, 24, 12, 16, 32, 32, 32, 16, 8, 24, 24, 8, 24, 42, 28, 32, 16, 12, 24, 32, 16, 24, 24, 8, 24, 36 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Number of divisors of the n-th oblong number. - Ray Chandler, Jun 23 2008 Number of positive solutions (x,y) for which n/x + (n+1)/y = 1. - Michel Lagneau, Jan 16 2014 LINKS Ray Chandler, Table of n, a(n) for n = 1..10000 FORMULA a(n) = A000005(n)*A000005(n+1) = A000005(n*(n+1)) = A000005(A002378(n)) = 2*A063123(n). MAPLE with(numtheory): seq(tau(n)*tau(n+1), n=1..73); # Zerinvary Lajos, Jan 22 2007 PROG (MAGMA) [ NumberOfDivisors(n^2+n) : n in [1..100]]; // Vincenzo Librandi, Apr 03 2011 (PARI) a(n) = numdiv(n^2+n); \\ Michel Marcus, Jan 11 2020 CROSSREFS Cf. A063440, A083539. Sequence in context: A133691 A111973 A161655 * A128558 A090346 A267460 Adjacent sequences:  A092514 A092515 A092516 * A092518 A092519 A092520 KEYWORD nonn,changed AUTHOR Reinhard Zumkeller, Apr 06 2004 EXTENSIONS Extended by Ray Chandler, Jun 23 2008 STATUS approved

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Last modified January 21 05:23 EST 2020. Contains 331104 sequences. (Running on oeis4.)