A382228 Smallest k such that k^3 is the sum of n consecutive primes.
2, 11, 268, 59, 22, 81, 58, 247, 56, 41, 210, 73, 46, 81, 258, 41, 70, 313, 28, 633, 156, 329, 206, 19, 492, 23, 48, 2285, 108, 349, 72, 165, 116, 221, 236, 187, 44, 1083, 82, 295, 34, 347, 54, 35, 548, 23, 32, 2357, 1170, 37, 632, 813, 1590, 277, 1972, 177
Offset: 2
Keywords
Examples
a(2)=2 : 2^3 = 8 = 3 + 5. a(3)=11 : 11^3 = 1331 = 439 + 443 + 449. a(4)=268 : 268^3 = 19248832 = 4812191 + 4812193 + 4812209 + 4812239.
Links
- David Dewan, Table of n, a(n) for n = 2..200
Programs
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Mathematica
a[n_]:=Do[mid=PrimePi[k^3/n];toTest=Prime[Range[Max[mid-n,1],mid+n]]; t=Total/@Partition[toTest,n,1];If[MemberQ[t,k^3],Return[k]], {k,2,Infinity}]; a/@Range[2, 10]
Formula
A382227(n) = a(n)^3.
Comments