[go: up one dir, main page]

login
A023567
Convolution of A023531 and primes.
1
0, 2, 3, 5, 9, 14, 18, 24, 32, 39, 51, 57, 71, 85, 94, 108, 124, 142, 152, 176, 193, 205, 229, 249, 271, 295, 315, 336, 364, 386, 408, 444, 468, 490, 526, 561, 583, 617, 663, 681, 717, 745, 781, 831, 862, 894, 924, 968, 1006, 1050, 1100, 1138, 1174
OFFSET
1,2
LINKS
FORMULA
a(n) = Sum_{i=0..n-1} A023531(n-i)*p(i+1) where p(i) is the i-th prime.
MAPLE
Primes:= select(isprime, [2, seq(i, i=3..1000, 2)]):
seq(add(Primes[n - i*(i+3)/2], i=1..floor((sqrt(1+8*n)-3)/2)), n=2..nops(Primes)); # Robert Israel, Dec 28 2015
PROG
(PARI) vector(20, x, c=0; j=x; t=3; while(j>1, c+=prime(j-1); j-=t; t+=1); c)
CROSSREFS
Sequence in context: A005244 A058541 A023672 * A076027 A280204 A240841
KEYWORD
nonn
EXTENSIONS
Corrected (term 781 was missing) by Jeremy Gardiner, Feb 05 2014
STATUS
approved