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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 (list; graph; refs; listen; history; text; internal format)
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

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Last modified May 17 12:55 EDT 2021. Contains 343971 sequences. (Running on oeis4.)