A215283 Row sums of triangle A215200.

1, 1, 2, 2, 0, 2, 2, 0, 6, 2, 6, 0, 2, 4, 4, 8, 4, 0, 8, 0, 0, 2, 4, 0, 14, 6, 2, 0, -2, 4, 8, 0, 2, 4, 12, 12, 4, 6, 10, 0, 10, 4, 8, 0, 2, 4, 6, 0, 32, 2, 12, 0, 0, 2, 12, 0, 2, 2, 18, 0, 2, 8, 2, 32, 10, 8, 8, 0, 0, 4, 12, 0, -2, 10, 6, 0, 0, 4, 18, 0, 42

Offset

1,3

Comments

The unsigned version of A215200 is A054521 which has as row sums the Euler totient function A000010.

Links

Robert Israel, Table of n, a(n) for n = 1..10000

Formula

a(n) = Sum_{k=1..n} (n-k | k) where (i | j) is the Kronecker symbol.

Maple

f:= n -> add(numtheory:-jacobi(n-k, k), k=1..n); # Robert Israel, Mar 11 2018

Mathematica

a[n_] := Sum[ KroneckerSymbol[n - k, k], {k, 1, n}]; Table[a[n], {n, 1, 81}] (* Jean-François Alcover, Jul 02 2013 *)

Prog

(Sage)
def A215200_row(n): return [kronecker_symbol(n-k, k) for k in (1..n)]
[sum(A215200_row(n)) for n in (1..81)]

Crossrefs

Cf. A000010, A054521, A215200, A215284.

Sequence in context: A225399 A035668 A307757 * A066518 A218491 A111165

Adjacent sequences: A215280 A215281 A215282 * A215284 A215285 A215286

Keyword

sign,look

Author

Peter Luschny, Aug 07 2012

Status

approved