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 A324381 Number of nonzero digits when the n-th highly composite number is written in primorial base: a(n) = A267263(A002182(n)). 4
 1, 1, 1, 1, 1, 1, 2, 2, 1, 1, 1, 2, 2, 2, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 1, 3, 3, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 2, 3, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 2, 3, 3, 2, 2, 3, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 2, 3, 2, 3, 2, 3, 2, 3, 4, 3, 3, 3, 3, 3, 2, 3, 3, 3, 2, 3, 3, 3, 4 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,7 LINKS Antti Karttunen, Table of n, a(n) for n = 1..10000 FORMULA a(n) = A267263(A002182(n)). a(n) <= A324382(n). EXAMPLE For n=12, A002182(12) = 240, which is written as "11000" in primorial base (A049345) because 240 = 1*A002110(4) + 1*A002110(3) = 210+30, thus a(12) = 2, as there are two nonzero digits. For n=18, A002182(18) = 2520 = "110000" in primorial base because 2520 = 1*A002110(5) + 1*A002110(4) = 2310+210, thus a(18) = 2. For n=26, A002182(26) = 45360 = "1670000" in primorial base because 45360 = 1*A002110(6) + 6*A002110(5) + 7*A002110(4), thus a(26) = 3, as there are three nonzero digits. PROG (PARI) A267263(n) = { my(s=0); forprime(p=2, , if(n%p, s++, if(n==0, return(s))); n\=p); }; \\ From A267263 A324381(n) = A267263(A002182(n)); CROSSREFS Cf. A002100, A002182, A049345, A267263, A324382. Cf. also A324341. Sequence in context: A184257 A275656 A228825 * A331383 A201208 A006513 Adjacent sequences:  A324378 A324379 A324380 * A324382 A324383 A324384 KEYWORD nonn AUTHOR Antti Karttunen, Feb 26 2019 STATUS approved

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Last modified May 25 22:48 EDT 2020. Contains 334597 sequences. (Running on oeis4.)