A280380 First occurrence of A280379(k) = n.

1, 2, 30, 46, 374, 2146, 5945, 14855, 24702

Offset

0,2

Comments

n < log(a(n)) for a(n) < 1.1*10^6.

Links

Table of n, a(n) for n=0..8.

Example

For prime(30)=113, A056171(113) = 14, A104272(12)=107 and A104272(13) = 127, so 14 - 12 = 2 (First occurrence).

Prog

(PARI) \\RR[x] is a list of Ramanujan primes, A104272.
{plimit=1.1*10^6; i=n=s=0;
forprime(p=2, plimit,
s++;
if(p==RR[n+1], n++);
if(i==s-primepi(floor(p/2))-n, print(i, " ", s); i++)
)
}

Crossrefs

Cf. A056171, A104272.

Sequence in context: A105962 A113695 A098827 * A184238 A285220 A078208

Adjacent sequences: A280377 A280378 A280379 * A280381 A280382 A280383

Keyword

nonn

Author

John W. Nicholson, Jan 09 2017

Status

approved