A093457 Product of primes in the range [T(n-1) + 1, T(n - 1) + n], where T(n) is the n-th triangular number.

1, 6, 5, 7, 143, 323, 23, 899, 65231, 2491, 3599, 347261, 583573, 1009091, 1317919, 16637, 428448457, 4273697, 5605027, 1445140189, 2445956099, 3368562317, 4927316309, 6454166203, 9473323417, 13508676341, 17347785757, 8989229423381

Offset

1,2

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Example

a(5) = 11*13 = 143.

Mathematica

Do[k = 1; Do[If[PrimeQ[i], k = k*i], {i, Binomial[n, 2] + 1, Binomial[n, 2] + n}]; Print[k], {n, 1, 30}] (* Ryan Propper, Jun 22 2005 *)
Join[{1, 6}, Table[With[{t=(n(n+1))/2}, Times@@Select[Range[t+1, t+n], PrimeQ]], {n, 2, 30}]]  (* Harvey P. Dale, Jan 18 2025 *)

Crossrefs

Cf. A093455, A093456.

Sequence in context: A266077 A019167 A019324 * A195446 A262993 A201764

Adjacent sequences: A093454 A093455 A093456 * A093458 A093459 A093460

Keyword

nonn

Author

Amarnath Murthy, Apr 03 2004

Extensions

More terms from Ryan Propper, Jun 22 2005

Status

approved