A023567

[Max]

Jeremy Gardiner wrote:
> Sorry, I am probably being dim here, but please could someone explain 
> how A023567 is calculated?
> 
> Thanks,
> Jeremy Gardiner
> 
> A023567  0,2,3,5,9,14,18,24,32,39,51,57,71,85,94,108,124,142,152,176,
> Convolution of A023531 and primes.
> 
> A023531  1,0,1,0,0,1,0,0,0,1,0,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,0,1,0,0
> a(n) = 1 if n of form m(m+3)/2, otherwise 0.
> 

I believe A023567(n) = \sum_{i=0}^{n-1} A023531(n-i)*p(i+1)
where p(i) is the i-th prime.

It's strange that A023531(0)=1 is not used in this calculation.

Max