A350193 Indices that give distinct values of A350090 in the order in which they appear.

0, 1, 5, 7, 22, 33, 124, 187, 757, 852, 876, 1149, 1541, 5951, 6767, 8454, 10067, 15555, 20272, 29751, 51721, 59662, 89055, 90088, 92489, 161673, 207737, 217341, 225622, 361054, 452639, 530990, 560684, 669999, 733454, 1000067, 1866828, 2090121, 2464677, 3148962

Offset

1,3

Links

Table of n, a(n) for n=1..40.

Mathematica

With[{s = Table[Count[Range[0, n - 1], _?(IntegerQ@ Sqrt[4 # + 1] &[(3 n (n + 1) + 1) - (3 # (# + 1) + 1)] &)], {n, 0, 2^10}]}, Map[-1 + FirstPosition[s, #][[1]] &, DeleteDuplicates@ s]] (* Michael De Vlieger, Dec 19 2021, after Amiram Eldar at A350090 *)

Crossrefs

Cf. A002378, A003215, A350090, A350120, A350192.

Sequence in context: A165144 A084164 A036498 * A248086 A076409 A294154

Adjacent sequences: A350190 A350191 A350192 * A350194 A350195 A350196

Keyword

nonn

Author

Michel Marcus, Dec 19 2021

Extensions

a(1) = 0 inserted by and more terms from Jinyuan Wang, Dec 19 2021

Status

approved