A004099 Sum of digits of Euler numbers.

1, 1, 1, 2, 5, 7, 7, 11, 17, 25, 13, 29, 29, 34, 46, 38, 41, 61, 61, 65, 62, 70, 85, 74, 83, 88, 91, 110, 113, 124, 106, 128, 170, 142, 157, 164, 128, 178, 172, 146, 176, 178, 178, 209, 206, 214, 247, 218, 263, 268, 235, 335, 284, 259, 295, 254, 278, 295, 283, 254, 308, 313

Offset

0,4

Links

Chai Wah Wu, Table of n, a(n) for n = 0..10000

Formula

a(n) = A007953(A000111(n)).

Maple

b:= proc(n, k) option remember; `if`(k=0,
     `if`(n=0, 1, 0), b(n, k-1)+b(n-1, n-k))
    end:
a:= proc(n) option remember;
      add(i, i=convert(b(n$2), base, 10))
    end:
seq(a(n), n=0..100);  # Alois P. Heinz, Apr 17 2023

Prog

(Python)
from itertools import accumulate, islice
def A004099_gen(): # generator of terms
    yield from (1, 1)
    blist = (0, 1)
    while True:
        blist = tuple(accumulate(reversed(blist), initial=0))
        yield sum(int(d) for d in str(blist[-1]))
A004099_list = list(islice(A004099_gen(), 30)) # Chai Wah Wu, Apr 17 2023

Crossrefs

Cf. A000111, A007953.

Sequence in context: A254340 A120303 A093413 * A084959 A021799 A154848

Adjacent sequences: A004096 A004097 A004098 * A004100 A004101 A004102

Keyword

nonn,base

Author

N. J. A. Sloane

Status

approved