A365899 Numbers k such that A073734(k) is neither squarefree nor a prime power.

2935, 5446, 5910, 9093, 11068, 15713, 15795, 18829, 19984, 23669, 25794, 26386, 33619, 36370, 36498, 41560, 41779, 46911, 48184, 48231, 48604, 50349, 50835, 53082, 53253, 53760, 54758, 56524, 58144, 58836, 59600, 60390, 60533, 63181, 64979, 65226, 65867, 66449

Offset

1,1

Comments

Subset of A073735.

A073734(a(n)) = GCD(A064413(a(n)-1), A064413(a(n))) is in A126706.

Links

Michael De Vlieger, Table of n, a(n) for n = 1..10000

Michael De Vlieger, Mathematica code for this sequence, based on Lagarias-Rains-Sloane 2002 paper, pages 4-5.

J. C. Lagarias, E. M. Rains and N. J. A. Sloane, The EKG sequence, Exper. Math. 11 (2002), 437-446; arXiv:math/0204011 [math.NT], 2002.

Index entries for sequences related to EKG sequence

Example

Table of first terms and how they relate to b(n) = A073735(n) and EKG(n) = A064413(n).
   n   m=a(n)  b(m)          EKG(m-1)  EKG(m)
  -------------------------------------------
   1    2935    20 = 2*2*5      3080    3060
   2    5446    20              5740    5660
   3    5910    20              6180    6140
   4    9093    20              9460    9440
   5   11068    12 = 2*2*3     11484   11472
   6   15713    52 = 2*2*13    16328   16276
   7   15795    12             16368   16356
   8   18829    36 = 2*2*3*3   19548   19476
   9   19984    63 = 3*3*7     20727   20664
  10   23669   116 = 2*2*29    24592   24476
  11   25794    56 = 2*2*2*7   26712   26656
  12   26386    68 = 2*2*17    27472   27268
  ...
  30   58836    18 = 2*3*3     60786   60778
  ...

Crossrefs

Cf. A064413, A073734, A073735, A126706.

Sequence in context: A345836 A345598 A345857 * A236196 A054832 A368650

Adjacent sequences: A365896 A365897 A365898 * A365900 A365901 A365902

Keyword

nonn

Author

Michael De Vlieger, Sep 28 2023

Status

approved