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 A351059 a(n) is the smallest number not yet in the sequence that has three digits in common with a(n-1), starting with a(1) = 1. 2
 1, 111, 10, 100, 102, 101, 103, 110, 104, 114, 14, 141, 41, 144, 124, 112, 12, 121, 21, 122, 120, 200, 20, 202, 201, 210, 211, 123, 113, 13, 131, 31, 133, 130, 300, 30, 303, 203, 220, 204, 222, 2, 1222, 23, 223, 32, 232, 132, 212, 125, 115, 15, 151, 51, 155, 105 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS See A350671 for the definition of "x has N digits in common with y". Terms computed by Claudio Meller. LINKS Table of n, a(n) for n=1..56. EXAMPLE a(2) = 111 because it is the smallest number that has exactly three digits in common with a(1) = 1; similarly, a(3) = 10 because it is the smallest number that is not already in the sequence that has exactly three digits in common with a(2) = 111 and a(4) = 100 because it has three digits in common with a(3)= 10. PROG (Python) from itertools import islice def c(s, t): return sum(t.count(si) for si in s) def agen(): # generator of terms an, target, seen, mink = 1, "1", {1}, 2 while True: yield an k = mink while k in seen or c(str(k), target) != 3: k += 1 an, target = k, str(k) seen.add(an) while mink in seen: mink += 1 print(list(islice(agen(), 56))) # Michael S. Branicky, Jan 30 2022 (PARI) isok(k, d, va) = {if (#select(x->(x==k), va), return(0)); my(dk=digits(k)); sum(i=1, #dk, #select(x->(x==dk[i]), d)) == 3; } lista(nn) = {my(va = vector(nn)); va = 1; for (n=2, nn, my(k=1, d = digits(va[n-1])); while(!isok(k, d, va), k++); va[n] = k; ); va; } \\ Michel Marcus, Jan 31 2022 CROSSREFS Cf. A350444, A350445, A350671, A350672. Sequence in context: A123698 A123727 A282915 * A279800 A282360 A279941 Adjacent sequences: A351056 A351057 A351058 * A351060 A351061 A351062 KEYWORD nonn,base AUTHOR Rodolfo Kurchan, Jan 30 2022 STATUS approved

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Last modified May 28 06:10 EDT 2023. Contains 362992 sequences. (Running on oeis4.)