[seqfan] Re: problems with A022920

[M. F. Hasler]

On Thu, Aug 6, 2015 at 8:26 AM, David Corneth <davidacorneth at gmail.com>
wrote:

> Shouldn't the name of A022920 be changed such that not every second element
> is 0? For example
> Number of solutions to c(1)p(4)+...+c(2n+1)p(2n+4) = 2, where c(i) = +-1
> for i>1, c(1) = 1, p(i) = primes.
>


The analogue with -1 and -2 on the r.h.s. seem not yet in OEIS, I propose
them as
https://oeis.org/draft/A261044
https://oeis.org/draft/A261045
but while I left the first proposal in the "aerated" version as the old
ones,
I propose the second one in the condensed version (a(n) using 2n-1 terms).
I don't know what should be preferred in this case*, thanks for feedback.
(The aerated version seems the more "natural" one, although one can of
course quickly figure out that every 2nd term is zero, and in an "unknown"
situation, maybe one would search for the sequence of nonzero terms
only...?)

PS: will also add the variants starting
with prime(1)=2 or prime(2)=3 or prime(3)=5, after discovering that these
existed for A022924 and A022920 ; I am now adding the (crucially!) missing
crossrefs there and elsewhere.

Regards,
Maximilian