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 A244852 Least number k > 0 such that 3^k begins with exactly n consecutive increasing digits. 3
 1, 17, 149, 146, 7997, 45419, 3972963, 27487124, 406680034 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Table of n, a(n) for n=1..9. EXAMPLE 3^17 = 129140163 begins with 2 consecutive increasing digits ('12'). Thus a(2) = 17. PROG (Python) def a(n): ..for k in range(1, 10**5): ....st = str(3**k) ....count = 0 ....if len(st) > n: ......for i in range(len(st)): ........if int(st[i]) == int(st[i+1])-1: ..........count += 1 ........else: ..........break ......if count == n: ........return k n = 0 while n < 10: ..print(a(n), end=', ') ..n += 1 CROSSREFS Cf. A244848, A244849, A244851. Sequence in context: A196780 A208506 A299599 * A064102 A161497 A162328 Adjacent sequences: A244849 A244850 A244851 * A244853 A244854 A244855 KEYWORD nonn,base,fini,full AUTHOR Derek Orr, Jul 07 2014 EXTENSIONS a(7)-a(9) from Hiroaki Yamanouchi, Jul 10 2014 STATUS approved

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Last modified February 22 06:02 EST 2024. Contains 370240 sequences. (Running on oeis4.)