A100543 Sum of first n terms of A_n (signed values).

0, 3, 3, 0, 10, 12, 1, 24, 25, 32, 116, 12, 412, 109, 126, 2389, 12497, 28772, 126, 72795, 247786, 770213, 159378001963452599312, 2169128, -26, 311, 378, 789, 10015050, 75, 74253544, 7881195, 2461717833658872781238383813854943728, 51, 17, -250, 855, 2, -29979, 3087, 215308, 123456790123456790123456790123456790123452, 132813776, 1086162642, 1836311902, 400276874544

Offset

1,2

Comments

Since the sequences in the OEIS occasionally change their initial terms (for editorial reasons), this is an especially ill-defined sequence! - N. J. A. Sloane, Jan 01 2005

The next term, a(47), is currently unknown. - Jianing Song, Oct 07 2018

Links

Table of n, a(n) for n=1..46.

Index entries for sequences whose definition involves A_n (or An).

Example

A000001 (Number of groups of order n) begins 0,... -> a(1) = 0
A000002 (Kolakoski sequence) begins 1, 2,... -> a(2) = 3
A000003 begins 1, 1, 1,... -> a(3) = 3
A000004 (The zero sequence) begins 0, 0, 0, 0,... -> a(4) = 0
A000005 (The number of divisors) begins 1, 2, 2, 3, 2, ... -> a(5) = 10
...
A000010 (Euler totient function) begins 1, 1, 2, 2, 4, 2, 6, 4, 6, ... so a(10) = 1 + 1 + 2 + 2 + 4 + 2 + 6 + 4 + 6 + 4 = 32.

Crossrefs

Cf. A031135, A031214, A039928.

Sequence in context: A120981 A298850 A262292 * A039928 A374828 A247889

Adjacent sequences: A100540 A100541 A100542 * A100544 A100545 A100546

Keyword

dumb,easy,sign

Author

Russ Cox

Extensions

Corrected and extended by C. Ronaldo (aga_new_ac(AT)hotmail.com), Dec 27 2004

a(1) changed from 1 to 0 by Jianing Song, Jul 02 2018

Extend by Jianing Song, Oct 07 2018

Status

approved