A218211 Number of n-digit primes that are the sum of six consecutive squares of nonnegative numbers.

0, 0, 4, 10, 15, 49, 147, 407, 1084, 3010, 8756, 25145, 73424, 215375, 631828, 1870092, 5562131, 16584139, 49630873, 148917071, 448088250

Offset: 1

Author

Martin Renner, Oct 23 2012

Keywords

• nonn
• base
• more

Comments

These are the primes of the form 91 + 42*k + 6*k^2.

Crossrefs

Cf. A027866, A027867, A218207, A218209, A218212.

Programs

Mathematica

n = 0; Table[cnt = 0; While[n++; p = 91 + 42*n + 6*n^2; p < 10^e, If[PrimeQ[p], cnt++]]; n--; cnt, {e, 14}] (* T. D. Noe, Oct 23 2012 *)

Formula

a(n) = A218212(n) - A218212(n-1)

Extensions

a(13)-a(21) from Chai Wah Wu, Feb 12 2018

a(2) changed back to 0 by Chai Wah Wu and N. J. A. Sloane, Feb 13 2018