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A030012 Euler transform of {1, primes}. 3
1, 3, 6, 14, 27, 58, 109, 216, 402, 760, 1390, 2550, 4569, 8178, 14408, 25280, 43850, 75685, 129436, 220226, 371906, 624840, 1043178, 1733108, 2863422, 4709222, 7706800, 12558213, 20372860, 32917707, 52971756, 84923643, 135640660, 215886778, 342419132 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Alois P. Heinz, Table of n, a(n) for n = 0..1000

N. J. A. Sloane, Transforms

MAPLE

with(numtheory): etr:= proc(p) local b; b:=proc(n) option remember; if n=0 then 1 else add(add(d*p(d), d=divisors(j)) *b(n-j), j=1..n)/n fi end end: c:= etr(k-> `if`(k<=1, k, ithprime(k-1))): a:= n-> c(n+1): seq(a(n), n=0..40);  # Alois P. Heinz, Sep 07 2008

MATHEMATICA

etr[p_] := Module[{b}, b[n_] := b[n] = If[n == 0, 1, Sum[Sum[d*p[d], {d, Divisors[j]}]*b[n-j], {j, 1, n}]/n]; b]; c = etr[If[# <= 1, #, Prime[#-1]]&]; a = c[#+1]&; Table[a[n], {n, 0, 35}] (* Jean-Fran├žois Alcover, Mar 10 2014, after Alois P. Heinz *)

CROSSREFS

Cf. A008578.

Sequence in context: A279986 A279474 A282756 * A001970 A006951 A224840

Adjacent sequences:  A030009 A030010 A030011 * A030013 A030014 A030015

KEYWORD

nonn

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified January 20 21:36 EST 2019. Contains 319336 sequences. (Running on oeis4.)