A076950 Smallest k such that nk-1 is a cube.

1, 1, 3, 7, 13, 21, 4, 43, 1, 73, 91, 111, 5, 2, 183, 211, 241, 7, 27, 343, 6, 421, 463, 507, 553, 189, 19, 1, 757, 813, 7, 931, 993, 1057, 196, 37, 36, 518, 126, 1483, 1561, 3, 8, 1807, 61, 1981, 2071, 2163, 140, 2353, 2451, 234, 2653, 91, 2863, 532, 9, 3193, 3307, 3423

Offset

1,3

Links

Table of n, a(n) for n=1..60.

Mathematica

Do[k = 1; While[ !IntegerQ[(n*k - 1)^(1/3)], k++ ]; Print[k], {n, 1, 59}]
skc[n_] :=Module[{k = 1}, While[! IntegerQ[Surd[ n*k - 1, 3]], k++]; k]; Array[skc, 60] (* Harvey P. Dale, Feb 15 2022 *)

Crossrefs

Sequence in context: A033551 A350296 A022777 * A169633 A069194 A100531

Adjacent sequences: A076947 A076948 A076949 * A076951 A076952 A076953

Keyword

nonn

Author

Amarnath Murthy, Oct 20 2002

Extensions

Edited and extended by Robert G. Wilson v, Oct 21 2002

Corrected and extended by Harvey P. Dale, Feb 15 2022

Status

approved