login
A335664
a(n) = f(n) - f(Sum_{k=1..n-1} a(k)) with a(1) = 1, where f = A000006.
0
1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 2, 1, 0, 0, 1, 1, 1, 2, 1, 1, 0, 1, 1, 1, 2, 1, 1, 0, 0, 1, 1, 1, 1, 2, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
OFFSET
1,12
MATHEMATICA
f[n_] := IntegerPart[Sqrt[Prime[n]]]; a[1] = 1; a[n_] := a[n] = f[n] - f[Sum[a[k], {k, 1, n - 1}]]; Array[a, 100] (* Amiram Eldar, Jul 09 2020 *)
PROG
(PARI) a=vector(10^2); a[1] = 1; for(n=2, #a, a[n] = sqrtint(prime(n)) - sqrtint(prime(sum(k=1, n-1, a[k])))); a
CROSSREFS
Sequence in context: A333382 A143379 A254605 * A269518 A219840 A343220
KEYWORD
nonn,easy
AUTHOR
Altug Alkan, Jul 09 2020
STATUS
approved