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A179655 Digital root of n-th abundant number. 0
3, 9, 2, 6, 3, 9, 4, 6, 3, 9, 2, 6, 3, 7, 9, 6, 8, 3, 7, 9, 6, 1, 3, 5, 9, 4, 6, 3, 9, 6, 3, 5, 9, 6, 3, 7, 9, 6, 3, 5, 9, 6, 3, 7, 9, 2, 6, 1, 3, 9, 4, 6, 8, 3, 9, 6, 3, 9, 6, 8, 3, 9, 2, 6, 1, 3, 9, 6, 3, 7, 9, 2, 6, 3, 5, 9, 6, 3, 7, 9, 6, 8, 1, 3, 9, 4, 6, 8, 3, 9, 2, 6, 3, 5, 9, 4, 6, 3, 9, 2, 6, 3, 9, 6, 8 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..105.

EXAMPLE

The 11th abundant number is 56. 5+6=11. 1+1=2. The digital root is 2.

MATHEMATICA

abQ[n_] := DivisorSigma[1, n] > 2 n; Mod[ Select[ Range@ 500, abQ], 9] /. 0 -> 9 (* Robert G. Wilson v, Aug 23 2010 *)

CROSSREFS

Cf. A005101.

Sequence in context: A155080 A010780 A309275 * A076420 A091473 A019675

Adjacent sequences:  A179652 A179653 A179654 * A179656 A179657 A179658

KEYWORD

nonn,base

AUTHOR

Jason G. Wurtzel, Jul 22 2010

EXTENSIONS

More terms from Robert G. Wilson v, Aug 23 2010

STATUS

approved

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Last modified October 21 16:25 EDT 2019. Contains 328302 sequences. (Running on oeis4.)