A353695 Indices of records in A353693.

1, 6, 15, 30, 70, 105, 210, 462, 770, 1155, 2145, 2310, 4290, 6006, 9282, 10010, 15015, 23205, 30030, 46410, 67830, 72930, 102102, 149226, 170170, 248710, 255255, 373065, 440895, 510510, 746130, 881790, 1193010, 1385670, 1874730, 1939938, 2624622, 3233230

Offset

1,2

Comments

The corresponding record values are 1, 2, 3, 12, 20, 45, 360, 504, 1400, 4725, 7425, 75600, 118800, 232848, 275184, 1078000, 5457375, 6449625, 174636000, 206388000, 269892000, 509652000, ...

Are all the terms squarefree (A005117)? If yes, then the calculation of terms of this sequence can be significantly sped up.

Links

Chai Wah Wu, Table of n, a(n) for n = 1..51

Example

The first 15 terms of A353693 are 1, 1, 1, 1, 1, 2, 1, 1, 1, 2, 1, 1, 1, 2 and 3. The record values, 1, 2 and 3, occur at 1, 6 and 15, the first 3 terms of this sequence.

Mathematica

f[n_] := Module[{k = 1}, While[! UnsameQ @@ FactorInteger[k*n][[;; , 2]], k++]; k]; fm = 0; s = {}; Do[f1 = f[n]; If[f1 > fm, fm = f1; AppendTo[s, n]], {n, 1, 10^4}]; s

Crossrefs

Cf. A005117, A353693.

Sequence in context: A011886 A212251 A262464 * A232169 A231814 A056497

Adjacent sequences: A353692 A353693 A353694 * A353696 A353697 A353698

Keyword

nonn

Author

Amiram Eldar, May 04 2022

Extensions

a(27)-a(38) from Chai Wah Wu, May 07 2022

Status

approved