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A203908 Multiplicative with a(p^e) = abs(p-e). 4
1, 1, 2, 0, 4, 2, 6, 1, 1, 4, 10, 0, 12, 6, 8, 2, 16, 1, 18, 0, 12, 10, 22, 2, 3, 12, 0, 0, 28, 8, 30, 3, 20, 16, 24, 0, 36, 18, 24, 4, 40, 12, 42, 0, 4, 22, 46, 4, 5, 3, 32, 0, 52, 0, 40, 6, 36, 28, 58, 0, 60, 30, 6, 4, 48, 20, 66, 0, 44, 24, 70, 1, 72, 36 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Density of nonzero terms is 0.72199023441955... = Product(1 - p^-p) where p runs over the primes. [Charles R Greathouse IV, Jan 23 2012]

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

MATHEMATICA

ar[p_, s_] := Abs[p-s]; arit[1] = 1; arit[n_] := Product[ar[FactorInteger[n][[i, 1]], FactorInteger[n][[i, 2]]], {i, Length[FactorInteger[n]]}]; Array[arit, 100] (* José María Grau Ribas, Jan 25 2012 *)

PROG

(Haskell)

a203908 n = product $ map abs $

            zipWith (-) (a027748_row n) (a124010_row n)

-- Reinhard Zumkeller, Dec 24 2013

CROSSREFS

Cf. A100717 (n such that a(n)=0).

Cf. A008473, A027748, A124010.

Sequence in context: A319997 A153733 A083218 * A334082 A307704 A139716

Adjacent sequences:  A203905 A203906 A203907 * A203909 A203910 A203911

KEYWORD

nonn,mult

AUTHOR

José María Grau Ribas, Jan 07 2012

STATUS

approved

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Last modified March 8 13:59 EST 2021. Contains 341949 sequences. (Running on oeis4.)