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A062671 Every divisor (except 1) contains the digit 5. 18
5, 25, 53, 59, 125, 151, 157, 251, 257, 265, 295, 353, 359, 457, 503, 509, 521, 523, 541, 547, 557, 563, 569, 571, 577, 587, 593, 599, 625, 653, 659, 751, 755, 757, 785, 853, 857, 859, 953, 1051, 1151, 1153, 1255, 1259, 1285, 1325, 1451, 1453, 1459, 1475, 1511 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
EXAMPLE
25 has divisors 1, 5 and 25, all of which (except 1) contain the digit 5.
MATHEMATICA
fQ[n_, dgt_] := Union[ MemberQ[#, dgt] & /@ IntegerDigits@ Rest@ Divisors@ n][[1]]; Select[ Range[2, 1500], fQ[#, 5] &] (* Robert G. Wilson v, Jun 11 2014 *)
PROG
(Magma) [k:k in [2..1500]| forall{d:d in Set(Divisors(k)) diff {1}| 5 in Intseq(d)}]; // Marius A. Burtea, Nov 07 2019
(Python)
from sympy import divisors
def ok(n): return all('5' in str(d) for d in divisors(n)[1:])
print(list(filter(ok, range(2, 1512)))) # Michael S. Branicky, May 25 2021
CROSSREFS
Sequence in context: A043106 A147184 A036133 * A225494 A139479 A078569
KEYWORD
base,easy,nonn
AUTHOR
Erich Friedman, Jul 04 2001
EXTENSIONS
Offset corrected by Amiram Eldar, Nov 07 2019
STATUS
approved

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Last modified July 22 12:22 EDT 2024. Contains 374499 sequences. (Running on oeis4.)