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A193471 Square array A(n,k) (n>=1, k>=0) read by antidiagonals: A(n,0) = 0 and A(n,k) is the least integer > A(n,k-1) that can be expressed as a sum of the first prime numbers divided by n. 1
0, 0, 2, 0, 1, 5, 0, 43, 5, 10, 0, 7, 127, 14, 17, 0, 1, 25, 167, 29, 28, 0, 1145, 2, 40, 213, 50, 41, 0, 4, 3758, 20, 82, 321, 80, 58, 0, 20, 11, 3932, 32, 110, 387, 119, 77, 0, 71, 41, 34, 4300, 88, 142, 457, 164, 100, 0, 1, 107, 55, 113, 4490, 212, 178, 531, 220, 129, 0, 7, 10 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1275

EXAMPLE

n\k  0   1   2    3    4     5     6    7

-----------------------------------------

1 |  0    2    5   10   17   28   41   58  A007504

2 |  0    1    5   14   29   50   80  119

3 |  0   43  127  167  213  321  387  457  A112270

4 |  0    7   25   40   82  110  142  178

5 |  0    1    2   20   32   88  212  296  A112271

6 |  0 1145 3758 3932 4300 4490 4684 5084

7 |  0    4   11   34  113  284  441  634  A112272

8 |  0   20   41   55   71   89  158  185

MAPLE

A193471_rect := proc(n, k) local j, i, L; L := NULL; j := 0;

while nops([L]) < k do add(ithprime(i)/n, i=1..j);

if type(%, integer) then L := L, % fi; j := j+1 od; L end:

seq(print(A193471_rect(n, 8)), n = 1..8);

MATHEMATICA

max = 12; rect[n_, k_] := Module[{j, i, L, s}, L = {}; j = 0; While[Length[L]<k, s = Sum[Prime[i]/n, {i, 1, j}]; If[IntegerQ[s], AppendTo[L, s]]; j = j+1]; L]; a[_, 0] = 0; a[n_, k_] := rect[n, max][[k+1]]; Table[a[n-k, k], {n, 1, max} , {k, 0, n-1}] // Flatten (* Jean-Fran├žois Alcover, Feb 25 2014, after Maple *)

CROSSREFS

Cf. A193470.

Sequence in context: A321619 A285212 A262948 * A182931 A260615 A293298

Adjacent sequences:  A193468 A193469 A193470 * A193472 A193473 A193474

KEYWORD

nonn,tabl

AUTHOR

Peter Luschny, Jul 29 2011

STATUS

approved

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Last modified August 24 14:24 EDT 2019. Contains 326284 sequences. (Running on oeis4.)