A073735 Numbers k such that the k-th term of the EKG sequence (A064413(k)) has more than one controlling prime.

579, 968, 1065, 1221, 1428, 1604, 2092, 2117, 2126, 2236, 2406, 2872, 2935, 3048, 3330, 3496, 4085, 4194, 4434, 4697, 4887, 5148, 5446, 5846, 5910, 6484, 6846, 7355, 7448, 7468, 7773, 7939, 8324, 8746, 8923, 8957, 9018, 9093, 9369, 10242, 10318

Offset

1,1

Comments

These are the k such that A073734(k) is not a prime power.

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, page 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

A064413(578) = 620, which is divisible by the primes 2, 5 and 31. So by definition, A064413(579) is the smallest number not already in A064413 that is divisible by 2, 5, or 31. This number is 610, which is divisible by both 2 and 5, so these are both called controlling primes of A064413(579).

Crossrefs

Cf. A064413, A064740, A073734.

Sequence in context: A107550 A097768 A286233 * A250727 A252985 A097769

Adjacent sequences: A073732 A073733 A073734 * A073736 A073737 A073738

Keyword

easy,nonn

Author

David Wasserman, Aug 06 2002

Status

approved