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A068543 Numbers n such that abs(prime(n)-n*tau(n)) < sqrt(n). 0
2, 3, 5, 26, 27, 33, 34, 171, 172, 175, 188, 1029, 1030, 1038, 1045, 1048, 1054, 1065, 1066, 1085, 1086, 1090, 1095, 1102, 1105, 1106, 1107, 39834, 39850, 39860, 39861, 39876, 39908, 39915, 39916, 39935, 39940, 39948, 39951, 39956, 39964, 39968 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..42.

MATHEMATICA

Reap[For[n = 2, n <= 40000, n++, If[Abs[Prime[n] - n*DivisorSigma[0, n]] < Sqrt[n], Sow[n]]]][[2, 1]] (* Jean-Fran├žois Alcover, Nov 07 2016 *)

CROSSREFS

Sequence in context: A280258 A181730 A024774 * A064026 A121264 A141566

Adjacent sequences:  A068540 A068541 A068542 * A068544 A068545 A068546

KEYWORD

easy,nonn

AUTHOR

Benoit Cloitre, Mar 22 2002

STATUS

approved

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Last modified February 24 19:27 EST 2020. Contains 332209 sequences. (Running on oeis4.)