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A303640
a(n) is the least k > n such that A007504(n) divides A007504(k).
1
3, 3, 9, 13, 33, 15, 121, 84, 103, 26, 259, 295, 433, 71, 111, 331, 317, 366, 649, 80, 283, 274, 429, 4542, 3071, 2138, 4241, 74, 761, 3083, 103, 1847, 1683, 3886, 1233, 470, 2359, 1182, 1797, 3431, 2037, 1767, 7543, 9106, 1867, 656, 5469, 6012, 12245, 2225
OFFSET
1,1
COMMENTS
Credit is given for Zak Seidov for doing the calculations.
LINKS
EXAMPLE
A007504(6)=41 and 41|328=A007504(15).
MAPLE
N:= 10^5: # to get all terms before the first term > N
A007504:= ListTools:-PartialSums([seq(ithprime(i), i=1..N)]):
found:= true:
for n from 1 while found do
found:= false;
for k from n+1 to N do
if A007504[k] mod A007504[n] = 0 then
found:= true;
A[n]:= k;
break
fi
od
od:
seq(A[i], i=1..n-2); # Robert Israel, May 02 2018
MATHEMATICA
a[n_] := For[tpn = Prime[Range[n]] // Total; tpk = 0; k = n+1, True, k++, tpk += Prime[k]; If[Divisible[tpk, tpn], Return[k]]]; Array[a, 50] (* Jean-François Alcover, Mar 22 2019 *)
CROSSREFS
Sequence in context: A083336 A225436 A183811 * A091328 A348402 A138383
KEYWORD
nonn
AUTHOR
J. M. Bergot, Apr 27 2018
EXTENSIONS
More terms from Alois P. Heinz, Apr 27 2018
STATUS
approved