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A072955 Suburban numbers: without b, r, s or u.

%I A072955 #8 Aug 19 2022 13:52:28
%S A072955 1,2,5,8,9,10,11,12,15,18,19,20,21,22,25,28,29,50,51,52,55,58,59,80,
%T A072955 81,82,85,88,89,90,91,92,95,98,99,1000000,1000001,1000002,1000005,
%U A072955 1000008,1000009,1000010,1000011,1000012,1000015,1000018,1000019,1000020
%N A072955 Suburban numbers: without b, r, s or u.
%D A072955 M. J. Halm, Sequences (Re)discovered, Mpossibilities 81 (Aug. 2002).
%H A072955 Michael S. Branicky, <a href="/A072955/b072955.txt">Table of n, a(n) for n = 1..10000</a>
%H A072955 Michael Halm, <a href="http://michaelhalm.tripod.com/id109.htm">Sequences (Re)discovered</a>.
%o A072955 (Python)
%o A072955 from num2words import num2words
%o A072955 from itertools import islice, product
%o A072955 def ok(n): return set(num2words(n)) & {"b", "r", "s", "u"} == set()
%o A072955 def agen(): # generator of terms < 10**304
%o A072955     base, pows = [k for k in range(1, 1000) if ok(k)], [1]
%o A072955     yield from ([0] if ok(0) else []) + base
%o A072955     for e in range(3, 304, 3):
%o A072955         if set(num2words(10**e)[4:]) & {"b", "r", "s", "u"} == set():
%o A072955             pows = [10**e] + pows
%o A072955             for t in product([0] + base, repeat=len(pows)):
%o A072955                 if t[0] == 0: continue
%o A072955                 yield sum(t[i]*pows[i] for i in range(len(t)))
%o A072955 print(list(islice(agen(), 66))) # _Michael S. Branicky_, Aug 19 2022
%Y A072955 Cf. A089590, A072956, A072957.
%K A072955 easy,nonn,word
%O A072955 1,2
%A A072955 _Michael Joseph Halm_, Aug 13 2002