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 A278226 Filter-sequence for primorial base: least number with the same prime signature as A276086(n). 21
 1, 2, 2, 6, 4, 12, 2, 6, 6, 30, 12, 60, 4, 12, 12, 60, 36, 180, 8, 24, 24, 120, 72, 360, 16, 48, 48, 240, 144, 720, 2, 6, 6, 30, 12, 60, 6, 30, 30, 210, 60, 420, 12, 60, 60, 420, 180, 1260, 24, 120, 120, 840, 360, 2520, 48, 240, 240, 1680, 720, 5040, 4, 12, 12, 60, 36, 180, 12, 60, 60, 420, 180, 1260, 36, 180, 180, 1260, 900, 6300, 72, 360, 360, 2520, 1800 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS This sequence can be used for filtering certain primorial base related sequences, because it matches only with any such sequence b that can be computed as b(n) = f(A276086(n)), where f(n) is any function that depends only on the prime signature of n (some of these are listed under the index entry for "sequences computed from exponents in ..."). Matching in this context means that the sequence a matches with the sequence b iff for all i, j: a(i) = a(j) => b(i) = b(j). In other words, iff the sequence b partitions the natural numbers to the same or coarser equivalence classes (as/than the sequence a) by the distinct values it obtains. Any such sequence should match where the result is computed from the nonzero digits (that may also be > 9) in the primorial base representation of n, but does not depend on their order. Some of these are listed on the last line of the Crossrefs section. LINKS Antti Karttunen, Table of n, a(n) for n = 0..30030 FORMULA a(n) = A046523(A276086(n)). PROG (Scheme) (define (A278226 n) (A046523 (A276086 n))) CROSSREFS Cf. A046523, A049345, A276086. Cf. also A278243. Similar sequences: A278222 (base-2 related), A069877 (base-10), A278236 (factorial base). Differs from A278236 for the first time at n=24, where a(24)=16, while A278236(24)=2. Sequences that partition N into same or coarser equivalence classes: A267263, A276150. Sequence in context: A109043 A054585 A278236 * A190940 A336869 A046203 Adjacent sequences:  A278223 A278224 A278225 * A278227 A278228 A278229 KEYWORD nonn,base AUTHOR Antti Karttunen, Nov 16 2016 STATUS approved

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Last modified June 23 23:00 EDT 2021. Contains 345402 sequences. (Running on oeis4.)