A352381 Numbers k such that no nonzero digit of 4*k divides 4*k.

14, 17, 19, 77, 89, 94, 95, 97, 127, 134, 139, 147, 149, 164, 167, 169, 177, 184, 190, 194, 195, 197, 199, 209, 215, 217, 227, 239, 244, 245, 247, 764, 767, 769, 827, 839, 844, 845, 847, 877, 884, 889, 899, 914, 917, 919, 925, 934, 940, 944, 947, 949, 959, 965, 967, 977, 989, 995, 997, 1259, 1264, 1267

Offset

1,1

Links

Table of n, a(n) for n=1..62.

Example

a(1) = 14 and 4*14 = 56 is not divisible by 5 or 6;
a(2) = 17 and 4*17 = 68 is not divisible by 6 or 8;
a(3) = 19 and 4*19 = 76 is not divisible by 7 or 6;
a(4) = 77 and 4*77 = 308 is not divisible by 3, 0 or 8; etc.
26 is not in the sequence as 4*26 = 104 is divisible by 1 (and 4).

Mathematica

q[n_] := AllTrue[IntegerDigits[4*n], # == 0 || !Divisible[4*n, #] &]; Select[Range[1270], q] (* Amiram Eldar, Mar 14 2022 *)

Prog

(Python)
def ok(n): return not any(4*n%int(d)==0 for d in set(str(4*n)) if d!='0')
print([k for k in range(1, 978) if ok(k)]) # Michael S. Branicky, Mar 14 2022

Crossrefs

Cf. A038772, A352379, A352380, A352382.

Sequence in context: A015877 A192290 A152010 * A243750 A379902 A046085

Adjacent sequences: A352378 A352379 A352380 * A352382 A352383 A352384

Keyword

base,nonn

Author

Eric Angelini and Carole Dubois, Mar 14 2022

Status

approved