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A238697 Quotients connected with the Banach matchboxes problem: Sum_{i=1..prime(n)-7} 2^(i-1)*binomial(i+2,3)/prime(n) (case 3). 9
0, 19, 197, 10481, 64027, 1980327, 259179061, 1257208799, 131286703021, 2756321451033, 12473384091267, 250290955437775, 21588599628845597, 1792050990708087027, 7763319803561678613, 620323392829436218475, 11365013042482773469559, 48487140450183407727097 (list; graph; refs; listen; history; text; internal format)
OFFSET

4,2

COMMENTS

See comment in A238693.

LINKS

Table of n, a(n) for n=4..21.

V. Shevelev, Banach matchboxes problem and a congruence for primes, arXiv:1110.5686 [math.HO], 2011.

MATHEMATICA

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

PROG

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

CROSSREFS

Cf. A238693.

Sequence in context: A141995 A210339 A097445 * A256639 A058370 A230012

Adjacent sequences:  A238694 A238695 A238696 * A238698 A238699 A238700

KEYWORD

nonn

AUTHOR

Vladimir Shevelev, Mar 03 2014

EXTENSIONS

More terms from Peter J. C. Moses, Mar 03 2014

STATUS

approved

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Last modified August 11 23:45 EDT 2020. Contains 336434 sequences. (Running on oeis4.)