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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.
9
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.
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); };
isA328587(n) = (A328578(n) < A257993(n));
CROSSREFS
Union of A328632 \ {0} and A328762.
Positions of negative terms in A328590.
Sequence in context: A068567 A316099 A082801 * A328632 A261435 A103590
KEYWORD
nonn
AUTHOR
Antti Karttunen, Oct 21 2019
STATUS
approved