

A244356


Numbers n such that n and n+1 are not divisible by any of their nonzero digits.


2



37, 46, 53, 56, 57, 58, 67, 68, 73, 78, 86, 97, 307, 337, 346, 358, 373, 376, 379, 388, 397, 406, 429, 433, 446, 457, 466, 469, 473, 477, 478, 489, 493, 498, 506, 507, 508, 538, 553, 556, 557, 558, 577, 578, 586, 587, 588, 596, 597, 598, 646, 656, 657, 658, 667, 668, 669
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OFFSET

1,1


COMMENTS

This is a subsequence of A038772.
All numbers end in a 3, 6, 7, 8, or 9.


LINKS

Robert Israel, Table of n, a(n) for n = 1..10000


EXAMPLE

37 is not divisible by 3 or 7 and 38 is not divisible by 3 or 8. Thus 37 is a member of this sequence.


MAPLE

filter:= proc(n) local L;
L:= convert(convert(n, base, 10), set) minus {0};
not ormap(t > n mod t = 0, L)
end proc:
B:= select(filter, {$1..1000}):
sort(convert(B intersect map(``, B, 1), list)); # Robert Israel, Dec 08 2019


PROG

(Python)
def a(n):
..for i in range(10**3):
....tot = 0
....for k in range(i, i+n):
......c = 0
......for b in str(k):
........if b != '0':
..........if k%int(b)!=0:
............c += 1
......if c == len(str(k))str(k).count('0'):
........tot += 1
....if tot == n:
......print(i, end=', ')
a(2)


CROSSREFS

Cf. A038772, A237766.
Sequence in context: A039351 A043174 A043954 * A159750 A108333 A231254
Adjacent sequences: A244353 A244354 A244355 * A244357 A244358 A244359


KEYWORD

nonn,base,look


AUTHOR

Derek Orr, Jun 26 2014


STATUS

approved



