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 A210326 Number of 5-divided words of length n over a 3-letter alphabet. 3
 0, 0, 0, 0, 0, 0, 15, 166, 1135, 5865, 26170, 105224, 396082, 1419981, 4916112 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,7 COMMENTS See A210109 for further information. Row sums of the following table which shows how many words of length n over a 3-letter alphabet are 5-divided in k>=1 different ways: 15; 103,43,20; 546,236,162,84,28,51,16,8,5; 2118,1211,848,480,... - R. J. Mathar, Mar 25 2012 REFERENCES Computed by David Scambler, Mar 19 2012 LINKS PROG (Python) from itertools import product, combinations, permutations def is5div(b):     for i, j, k, l in combinations(range(1, len(b)), 4):         divisions = [b[:i], b[i:j], b[j:k], b[k:l], b[l:]]         all_greater = True         for p, bp in enumerate(permutations(divisions)):             if p == 0: continue             if b >= "".join(bp): all_greater = False; break         if all_greater: return True     return False def a(n): return sum(is5div("".join(b)) for b in product("012", repeat=n)) print([a(n) for n in range(1, 10)]) # Michael S. Branicky, Aug 28 2021 CROSSREFS Cf. A210109, A210324, A210325. Sequence in context: A229406 A118093 A167615 * A016234 A160197 A055660 Adjacent sequences:  A210323 A210324 A210325 * A210327 A210328 A210329 KEYWORD nonn,more AUTHOR N. J. A. Sloane, Mar 20 2012 EXTENSIONS a(14)-a(15) from Michael S. Branicky, Aug 28 2021 STATUS approved

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Last modified May 17 17:52 EDT 2022. Contains 353778 sequences. (Running on oeis4.)