A238697 - OEIS

%I #12 Dec 06 2018 16:35:18

%S 0,19,197,10481,64027,1980327,259179061,1257208799,131286703021,

%T 2756321451033,12473384091267,250290955437775,21588599628845597,

%U 1792050990708087027,7763319803561678613,620323392829436218475,11365013042482773469559,48487140450183407727097

%N Quotients connected with the Banach matchboxes problem: Sum_{i=1..prime(n)-7} 2^(i-1)*binomial(i+2,3)/prime(n) (case 3).

%C See comment in A238693.

%H V. Shevelev, <a href="http://arxiv.org/abs/1110.5686">Banach matchboxes problem and a congruence for primes</a>, arXiv:1110.5686 [math.HO], 2011.

%t Array[Sum[2^(i - 1)*Binomial[i + 2, 3]/#, {i, # - 7}] &@ Prime@ # &, 18, 4] (* _Michael De Vlieger_, Dec 06 2018 *)

%o (PARI) a(n) = sum(i=1, prime(n)-7, 2^(i-1)*binomial(i+2,3))/prime(n); \\ _Michel Marcus_, Dec 06 2018

%Y Cf. A238693.

%K nonn

%O 4,2

%A _Vladimir Shevelev_, Mar 03 2014

%E More terms from _Peter J. C. Moses_, Mar 03 2014