A328587 Numbers n for which A257993(A276086(A276086(n))) is less than A257993(n), where A276086 converts the primorial base expansion of n into its prime product form, and A257993 returns the index of the least prime not present in its argument.

12, 24, 30, 42, 54, 60, 72, 84, 90, 102, 114, 120, 132, 144, 150, 162, 174, 180, 192, 204, 210, 216, 228, 246, 258, 276, 288, 306, 318, 336, 348, 366, 378, 396, 408, 420, 432, 444, 450, 462, 474, 480, 492, 504, 510, 522, 534, 540, 552, 564, 570, 582, 594, 600, 612, 624, 636, 648, 666, 678, 696, 708, 726, 738, 756, 768, 786, 798, 816

Offset

1,1

Comments

Numbers n for which A328578(n) is less than A257993(n).

All terms are multiples of 6. The final digit {0, 2, 4, 6, 8} of the decimal representation seems to be quite evenly distributed.

Other multiples of six are in A328586 and A328589.

210 is the first term not present in A328632.

Links

Antti Karttunen, Table of n, a(n) for n = 1..10000

Index entries for sequences related to primorial base

Prog

(PARI)
A257993(n) = { for(i=1, oo, if(n%prime(i), return(i))); }
A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
A328578(n) = A257993(A276086(A276086(n)));
isA328587(n) = (A328578(n) < A257993(n));

Crossrefs

Union of A328632 \ {0} and A328762.

Positions of negative terms in A328590.

Cf. A257993, A276086, A328578, A328585, A328586, A328588.

Sequence in context: A068567 A316099 A082801 * A328632 A261435 A103590

Adjacent sequences: A328584 A328585 A328586 * A328588 A328589 A328590

Keyword

nonn

Author

Antti Karttunen, Oct 21 2019

Status

approved