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 A171762 a(n) = Sum_{k=n^2+1..(n+1)^2-1} tau(k). 1
 4, 12, 22, 34, 44, 58, 72, 88, 100, 120, 126, 148, 164, 182, 196, 220, 228, 254, 264, 284, 304, 328, 338, 358, 382, 400, 420, 444, 442, 478, 494, 518, 544, 564, 562, 602, 622, 648, 652, 690, 684, 730, 740, 768, 790, 812, 828, 858, 870, 898, 920, 946, 958, 990 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Table of n, a(n) for n=1..54. FORMULA a(n) = A168011(n) - A168011(n-1) - A048691(n). - R. J. Mathar, Jan 25 2010 MAPLE A168011 := proc(n) add( numtheory[tau](k), k=1..n^2+2*n) ; end proc: A048691 := proc(n) numtheory[tau](n^2) ; end proc: A171762 := proc(n) A168011(n)-A168011(n-1)-A048691(n) ; end proc: seq(A171762(n), n=1..80) ; # R. J. Mathar, Jan 25 2010 MATHEMATICA Array[n \[Function] Sum[DivisorSigma[0, k], {k, n^2 + 1, (n + 1)^2 - 1}], 200] (* J. Mulder (jasper.mulder(AT)planet.nl), Jan 28 2010 *) CROSSREFS Cf. A000005, A048691, A168011. Sequence in context: A301263 A047956 A301228 * A210639 A301260 A301185 Adjacent sequences: A171759 A171760 A171761 * A171763 A171764 A171765 KEYWORD nonn,easy AUTHOR Giovanni Teofilatto, Dec 18 2009 EXTENSIONS Definition corrected by Giovanni Teofilatto, Dec 19 2009 More terms from R. J. Mathar and J. Mulder (jasper.mulder(AT)planet.nl), Jan 25 2010 STATUS approved

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Last modified September 7 15:37 EDT 2024. Contains 375730 sequences. (Running on oeis4.)