The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A362062 First index in A362061 where A001221(A362061(a(n))) = n. 2
 1, 3, 10, 52, 398, 4734, 78428, 1326821, 26386288, 645482585 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS Table of n, a(n) for n=0..9. PROG (Python) from sympy import primefactors from collections import Counter from itertools import count, islice def agen(): # generator of terms an, c, d, d2, k = 1, Counter(), dict(), dict(), 0 for n in count(1): if an in d: dpf = d[an] else: dpf, d2[dpf] = len(primefactors(an)), n c[dpf] += 1 an = c[dpf] if k in d2: yield d2[k]; k += 1 print(list(islice(agen(), 7))) # Michael S. Branicky, Apr 06 2023 (Python) from itertools import count from sympy import primenu def A362062(n): a, b, c = {}, {}, 1 for m in count(1): d = b[c] = b.get(c, primenu(c)) if d == n: return m c = a[d] = a.get(d, 0)+1 # Chai Wah Wu, Apr 07 2023 CROSSREFS Cf. A362061, A001221. Sequence in context: A309885 A363209 A052446 * A373284 A290489 A002873 Adjacent sequences: A362059 A362060 A362061 * A362063 A362064 A362065 KEYWORD nonn,more AUTHOR Scott R. Shannon, Apr 06 2023 EXTENSIONS a(9) from Chai Wah Wu, Apr 07 2023 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified August 14 18:14 EDT 2024. Contains 375166 sequences. (Running on oeis4.)