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 A238714 Final divisor of A238529(n). 1
 2, 3, 4, 5, 5, 7, 2, 3, 3, 11, 5, 13, 5, 7, 8, 17, 2, 19, 2, 10, 3, 23, 5, 5, 11, 9, 5, 29, 10, 31, 2, 5, 7, 11, 5, 37, 17, 7, 7, 41, 5, 43, 5, 11, 10, 47, 4, 7, 2, 11, 17, 53, 3, 7, 4, 13, 9, 59, 12, 61, 29, 11, 4, 11, 2, 67, 5, 17, 14, 71, 12, 73, 11, 3, 7, 5, 5 (list; graph; refs; listen; history; text; internal format)
 OFFSET 2,1 COMMENTS Conjecture:  Every integer greater than 1, except 6, is an element of the sequence. LINKS Tom Davis, Table of n, a(n) for n = 2..10001 EXAMPLE a(8) = 2, because 8 mod sopfr(8) = 8 mod 6 = 2, and 2 mod sopfr(2) = 2 mod 2 = 0, and 2 is the last divisor used. a(21) = 10, because 21 mod sopfr(21) = 21 mod 10 = 1, and 10 is the last divisor used. PROG (Python) def primfacs(n):    i = 2    primfac = []    while i * i <= n:        while n % i == 0:            primfac.append(i)            n = n / i        i = i + 1    if n > 1:        primfac.append(n)    return primfac def sopfr(n):    plist = list(primfacs(n))    l = len(plist)    s = 0    while l > 0:        s += plist[l - 1]        l -= 1    return s n = 2 max = 1000 lst = list() while n <= max:    rem = n    while rem > 1:        last = sopfr(rem)        rem = rem % last    lst.append("%i" % last)    n += 1 print lst CROSSREFS Cf. A238529. Sequence in context: A017855 A051598 A086993 * A289311 A029908 A081758 Adjacent sequences:  A238711 A238712 A238713 * A238715 A238716 A238717 KEYWORD nonn AUTHOR J. Stauduhar, Mar 03 2014 STATUS approved

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Last modified July 17 18:41 EDT 2019. Contains 325109 sequences. (Running on oeis4.)