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A236403
Numbers not in A236402.
4
11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 24, 25, 26, 27, 28, 29, 31, 32, 33, 34, 35, 36, 37, 38, 39, 41, 42, 43, 44, 45, 46, 47, 48, 49, 51, 52, 53, 54, 55, 56, 57, 58, 59, 61, 62, 63, 64, 65, 66, 67, 68, 69, 71, 72, 73, 74, 75, 76, 77, 78, 79, 81, 82, 83, 84, 85, 86, 87, 88, 89, 91, 92, 93, 94, 95, 96, 97, 98, 99, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119
OFFSET
1,1
COMMENTS
This sequence has density 0, since all numbers except a thin fraction have digits 0 through 18 in base 100. In particular, there are at most x^0.99782 members up to x for large enough x. (This can be improved.) - Charles R Greathouse IV, Jan 30 2014
Where does this first differ from A038687? - R. J. Mathar, Feb 03 2014
Is this a shifted version of A031954? - R. J. Mathar, Feb 03 2014
PROG
(PARI) is(n)=my(d=digits(n), S=Set(d), v=List()); for(i=2, #d, listput(v, 10*d[i-1]+d[i])); S=setunion(S, Set(v)); for(i=2, #d, if(!setsearch(S, d[i-1]+d[i]), return(1))); 0 \\ Charles R Greathouse IV, Mar 10 2021
(Python)
def ok(n):
s = str(n)
return not all(str(sum(map(int, s[i:i+2]))) in s for i in range(len(s)-1))
print(list(filter(ok, range(120)))) # Michael S. Branicky, Jun 11 2021
CROSSREFS
Subsequence of A052382.
Cf. A236402.
Sequence in context: A216589 A038687 A359983 * A293728 A070255 A267085
KEYWORD
nonn,base
AUTHOR
Eric Angelini, Jan 30 2014
EXTENSIONS
Missing a(82) added by Charles R Greathouse IV, Mar 10 2021
STATUS
approved