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A036433
Number of divisors is a digit in the base 10 representation of n.
2
1, 2, 14, 23, 29, 34, 46, 63, 68, 74, 76, 78, 88, 94, 116, 127, 128, 134, 138, 141, 142, 143, 145, 146, 164, 182, 184, 186, 189, 194, 196, 211, 214, 223, 227, 229, 233, 236, 238, 239, 241, 247, 248, 249, 251, 254, 257, 258, 261, 263, 268, 269, 271, 274, 277
OFFSET
1,2
COMMENTS
Invented by the HR concept formation program.
LINKS
S. Colton, Refactorable Numbers - A Machine Invention, J. Integer Sequences, Vol. 2, 1999, #2.
EXAMPLE
14 has 4 divisors and 4 is a digit in the base 10 representation of 14.
MATHEMATICA
Select[Range[300], MemberQ[IntegerDigits[#], DivisorSigma[0, #]]&] (* Harvey P. Dale, Sep 02 2013 *)
PROG
(Haskell)
a036433 n = a036433_list !! (n-1)
a036433_list = filter f [1..] where
f x = d < 10 && ("0123456789" !! d) `elem` show x where d = a000005 x
-- Reinhard Zumkeller, Mar 15 2012
(Python)
from sympy import divisor_count
A036433_list = []
for i in range(1, 10**5):
....d = divisor_count(i)
....if d < 10 and str(d) in str(i):
........A036433_list.append(i) # Chai Wah Wu, Jan 07 2015
CROSSREFS
Cf. A000005.
Sequence in context: A328217 A116639 A220274 * A172048 A226334 A109255
KEYWORD
base,nice,nonn
AUTHOR
Simon Colton (simonco(AT)cs.york.ac.uk)
STATUS
approved