A235775 a(n) = A047842(A047842(n)), say what you see, once repeated.

1011, 21, 1112, 1113, 1114, 1115, 1116, 1117, 1118, 1119, 1031, 1112, 3112, 3113, 3114, 3115, 3116, 3117, 3118, 3119, 102112, 3112, 22, 211213, 211214, 211215, 211216, 211217, 211218, 211219, 102113, 3113, 211213, 1213, 211314, 211315, 211316, 211317, 211318

Offset

0,1

Links

Reinhard Zumkeller, Table of n, a(n) for n = 0..10000

Example

a(10) = A047842(1011) = 1031;
a(11) = A047842(21) = 1112;
a(12) = A047842(1112) = 3112;
a(100) = A047842(2011) = 102112;
a(101) = A047842(1021) = 102112;
a(102) = A047842(101112) = 104112.

Prog

(Haskell)
a235775 = a047842 . a047842
(Python)
def A235775(n):
    s = str(n)
    s = ''.join(str(s.count(d))+d for d in sorted(set(s)))
    return int(''.join(str(s.count(d))+d for d in sorted(set(s)))) # Chai Wah Wu, Feb 12 2023

Crossrefs

Sequence in context: A266673 A055473 A317526 * A262865 A213315 A345906

Adjacent sequences: A235772 A235773 A235774 * A235776 A235777 A235778

Keyword

nonn,base

Author

Reinhard Zumkeller, Jan 15 2014

Status

approved