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A132810
Smallest sum of n consecutive odd primes which is a multiple of n.
5
3, 8, 15, 36, 395, 72, 119, 240, 2349, 300, 539, 276, 923, 714, 435, 496, 629, 702, 2375, 1120, 1995, 1144, 3979, 3192, 3925, 2938, 9531, 1960, 10063, 2670, 3441, 4448, 5907, 6358, 9835, 4464, 5069, 3610, 13533, 4000, 6273, 4410, 21113, 12012, 8325, 8142
OFFSET
1,1
FORMULA
Let A132809(n)=prime(i). Then a(n)= sum(j=i...i+n-1) prime(j). - R. J. Mathar, Nov 27 2007
EXAMPLE
a(5)=395, associated with A132809(5)=71=prime(20) as the first of the 5 consecutive primes, is the smallest sum of 5 consecutive odd primes which is divisible by n=5.
MATHEMATICA
Table[Module[{nn=n, ncop}, ncop=Total/@Partition[Prime[Range[2, 2500]], nn, 1]; SelectFirst[ ncop, Mod[#, nn]==0&]], {n, 50}] (* Harvey P. Dale, Jan 17 2023 *)
CROSSREFS
Sequence in context: A032255 A137475 A176433 * A032159 A174982 A032064
KEYWORD
easy,nonn
AUTHOR
Enoch Haga, Sep 01 2007
EXTENSIONS
The example does not match the sequence. Also the offset for all of this bunch of sequences should probably be 1. - N. J. A. Sloane, Sep 13 2007
Edited by R. J. Mathar, Nov 27 2007
STATUS
approved