A043295 Sum of digits of numerator of Bernoulli number B(2n).

1, 1, 1, 1, 5, 16, 7, 17, 28, 20, 26, 34, 25, 47, 53, 44, 79, 79, 88, 82, 88, 86, 104, 146, 113, 152, 145, 164, 152, 158, 160, 206, 164, 190, 193, 250, 205, 262, 259, 341, 257, 278, 331, 301, 323, 362, 295, 356, 349, 355, 346, 359, 380, 475, 457, 449, 415, 464

Offset

1,5

Links

Table of n, a(n) for n=1..58.

Formula

a(n) = A007953(A000367(n)). - Michel Marcus, Feb 16 2021

Example

Numerator(B(2*9))=43867 and 4+3+8+6+7=28 hence a(9)=28.

Mathematica

Total[IntegerDigits[Numerator[#]]]&/@BernoulliB[2*Range[60]] (* Harvey P. Dale, Oct 28 2022 *)

Prog

(PARI) a(n) = sumdigits(numerator(bernfrac(2*n))); \\ Michel Marcus, Feb 16 2021
(Python)
from sympy import bernoulli
def a(n): return sum(map(int, str(abs(bernoulli(2*n).numerator()))))
print([a(n) for n in range(1, 59)]) # Michael S. Branicky, Jun 03 2021

Crossrefs

Cf. A000367, A007953, A043296.

Sequence in context: A302062 A161846 A069937 * A063927 A195869 A101752

Adjacent sequences: A043292 A043293 A043294 * A043296 A043297 A043298

Keyword

base,easy,nonn

Author

Benoit Cloitre, Mar 24 2002

Status

approved