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 A278224 a(n) = A046523(A048673(n)). 9
 1, 2, 2, 2, 4, 8, 6, 6, 2, 2, 2, 2, 4, 2, 12, 2, 6, 6, 12, 32, 12, 12, 6, 12, 4, 6, 12, 12, 16, 2, 2, 6, 6, 2, 6, 2, 6, 6, 2, 6, 6, 2, 24, 2, 24, 12, 8, 6, 2, 6, 48, 6, 30, 12, 6, 2, 6, 2, 2, 6, 6, 24, 30, 6, 60, 12, 36, 6, 2, 12, 2, 12, 24, 6, 6, 24, 72, 128, 30, 12, 2, 6, 12, 24, 2, 2, 30, 48, 4, 2, 6, 2, 6, 48, 16, 96, 6, 30, 2, 6, 12, 6, 24, 30, 2, 2, 6 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS This sequence works as a "sentinel" for sequence A048673 by matching to any other sequence that is obtained as f(A048673(n)), where f(n) is any function that depends only on the prime signature of n (see the index entry for "sequences computed from exponents in ..."). As of Nov 11 2016 no such sequences were present in the database. LINKS Antti Karttunen, Table of n, a(n) for n = 1..10500 FORMULA a(n) = A046523(A048673(n)). PROG (Scheme) (define (A278224 n) (A046523 (A048673 n))) (Python) from sympy import factorint, nextprime from operator import mul def P(n):     f = factorint(n)     return sorted([f[i] for i in f]) def a046523(n):     x=1     while True:         if P(n) == P(x): return x         else: x+=1 def a048673(n):     f = factorint(n)     return 1 if n==1 else (1 + reduce(mul, [nextprime(i)**f[i] for i in f]))//2 def a(n): return a046523(a048673(n)) print([a(n) for n in range(1, 101)]) # Indranil Ghosh, Jun 12 2017 CROSSREFS Cf. A046523, A048673, A278223. Sequence in context: A286613 A229061 A339464 * A161421 A306337 A326022 Adjacent sequences:  A278221 A278222 A278223 * A278225 A278226 A278227 KEYWORD nonn AUTHOR Antti Karttunen, Nov 16 2016 STATUS approved

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Last modified September 26 09:05 EDT 2021. Contains 347664 sequences. (Running on oeis4.)