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A280380 First occurrence of A280379(k) = n. 0

%I

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

%N First occurrence of A280379(k) = n.

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

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

%o (Pari) \\RR[x] is a list of Ramanujan primes, A104272.

%o {plimit=1.1*10^6;i=n=s=0;

%o forprime(p=2,plimit,

%o s++;

%o if(p==RR[n+1],n++);

%o if(i==s-primepi(floor(p/2))-n,print(i," ",s);i++)

%o )

%o }

%Y Cf. A056171, A104272.

%K nonn

%O 0,2

%A _John W. Nicholson_, Jan 09 2017

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Last modified September 20 16:30 EDT 2019. Contains 327242 sequences. (Running on oeis4.)