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A215283 Row sums of triangle A215200. 4
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 (list; graph; refs; listen; history; text; internal format)
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-Fran├žois 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

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Last modified October 26 14:28 EDT 2021. Contains 348267 sequences. (Running on oeis4.)