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 A238530 Position of first occurrence of n in A238529 (Recursive depth of n modulo sopfr(n)). 2
 2, 8, 22, 166, 778, 4962, 29922, 179682, 688078, 7060198, 42361338, 674524645 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS EXAMPLE The depth of 22 is 3 because 22->9->3, that is, 22 mod (11 + 2) = 9, 9 mod (3 + 3) = 3, and 3 mod (3) = 0, and 22 is the smallest number to have a depth of 3. a(10) = 7060198, because 7060198->3530097->392185->78417->8665->1713->565->93->25->5 PROG (Python) def primfacs(n):     i = 2     primfacs = []     while i * i <= n:         while n % i == 0:             primfacs.append(i)             n = n / i         i = i + 1     if n > 1:         primfacs.append(n)     return primfacs def sopfr(n):     plist = list(primfacs(n))     l = len(plist)     s = 0     while l > 0:         s += plist[l - 1]         l -= 1     return s def sd(n):     d = 1     s = n % sopfr(n)     if s > 1:         d += sd(s)     return d n=2 max=1000 rec = 0 lst = [] while n <= max:     r = sd(n)     if r > rec:         lst.append(n)         rec = r     n += 1 print(lst) CROSSREFS Sequence in context: A300370 A191643 A151356 * A303287 A321068 A158466 Adjacent sequences:  A238527 A238528 A238529 * A238531 A238532 A238533 KEYWORD nonn,more AUTHOR J. Stauduhar, Feb 28 2014 EXTENSIONS a(12) from Michel Marcus, Mar 26 2014 STATUS approved

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Last modified July 7 12:47 EDT 2022. Contains 355148 sequences. (Running on oeis4.)