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 A194281 Number of cycles under iteration of sum of cubes of digits in base b. 2
 0, 1, 0, 1, 1, 8, 1, 4, 4, 6, 2, 12, 3, 7, 8, 7, 3, 16, 3, 6, 7, 7, 4, 14, 1, 8, 11, 7, 2, 20, 7, 5, 16, 9, 7, 18, 4, 7, 10, 6, 4, 24, 5, 5, 13, 6, 7, 25, 2, 10, 20, 6, 5, 23, 7, 7, 17, 9, 7, 29, 3, 10, 14, 14, 6, 21, 7, 10, 17, 18, 9, 30, 8, 10, 24, 12, 4, 28, 4, 19, 12, 11, 6, 36 (list; graph; refs; listen; history; text; internal format)
 OFFSET 2,6 COMMENTS If b>=2 and n >= 2*b^3, then S(n,3,b)0 do B:=S(A[1], 3, b); C:=[seq(B[i], i=1..nops(B)-1)]: if nops(C)<>1 then Z:={op(Z), C}: fi: A:=A minus {op(B)}; od: return(nops(Z)); end: # Martin Renner, Aug 24 2011 PROG (Sage) def A194281(n):     cycle_mins = set()     seen = {}     for i in (1..2*n**3):         if i not in seen:             path = []             while not i in path and not i in seen:                 path.append(i)                 i = sum(d**3 for d in i.digits(base=n))             if i not in seen:                 m = min(path[path.index(i):])                 if sf(m) != m: cycle_mins.add(m)             else: m = seen[i]             for p in path: seen[p] = m     return len(cycle_mins) # D. S. McNeil, Aug 24 2011 CROSSREFS Cf. A193594, A194025. Sequence in context: A197590 A154190 A019981 * A117038 A172168 A321095 Adjacent sequences:  A194278 A194279 A194280 * A194282 A194283 A194284 KEYWORD nonn,base AUTHOR Martin Renner, Aug 22 2011 STATUS approved

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Last modified August 12 11:10 EDT 2020. Contains 336438 sequences. (Running on oeis4.)