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A137441
Partial sums of partial sums of PrimePi(k).
1
0, 1, 4, 9, 17, 28, 43, 62, 85, 112, 144, 181, 224, 273, 328, 389, 457, 532, 615, 706, 805, 912, 1028, 1153, 1287, 1430, 1582, 1743, 1914, 2095, 2287, 2490, 2704, 2929, 3165, 3412, 3671, 3942, 4225, 4520, 4828, 5149, 5484, 5833, 6196, 6573, 6965, 7372, 7794
OFFSET
1,3
LINKS
Alois P. Heinz, Table of n, a(n) for n = 1..10000 (first 1000 terms from Harvey P. Dale)
FORMULA
a(n) = partial sum of A046992 = partial sum of partial sum of PrimePi(k) = partial sum of partial sum of A000720(k) = Sum_{j=1..n} (Sum_{k=1..j} PrimePi(k)).
a(n) = Sum_{i=1..n} (n+1-i)*pi(i), where pi = A000720. - Ridouane Oudra, Aug 31 2019
MAPLE
A000720 := proc(n) option remember ; numtheory[pi](n) ; end: A046992 := proc(n) option remember ; add( A000720(i), i=1..n) ; end: A137441 := proc(n) add( A046992(i), i=1..n) ; end: seq(A137441(n), n=1..80) ; # R. J. Mathar, Apr 23 2008
# second Maple program:
b:= proc(n) option remember; `if`(n<1, [0$2],
(p-> p+[numtheory[pi](n+1), p[1]])(b(n-1)))
end:
a:= n-> b(n)[2]:
seq(a(n), n=1..49); # Alois P. Heinz, Oct 07 2021
MATHEMATICA
Accumulate[Accumulate[PrimePi[Range[50]]]] (* Harvey P. Dale, Feb 17 2013 *)
CROSSREFS
Sequence in context: A008023 A008055 A301019 * A005744 A027367 A348238
KEYWORD
easy,nonn
AUTHOR
Jonathan Vos Post, Apr 17 2008
EXTENSIONS
More terms from R. J. Mathar, Apr 23 2008
STATUS
approved