A061681 a(0)=1; a(n) = a(n-1) + lead(a(n-1)) for n > 0 where for an integer x lead(x) is the leading digit in base 10.

1, 2, 4, 8, 16, 17, 18, 19, 20, 22, 24, 26, 28, 30, 33, 36, 39, 42, 46, 50, 55, 60, 66, 72, 79, 86, 94, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134

Offset: 0

Author

Reinhard Zumkeller, Jun 18 2001

Keywords

• base
• easy
• nonn
• nice
• look

Examples

			a(100)=176; a(307)=996; a(1000)=1697; a(3132)=9995; a(10000)=16871.
		

Links

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

Programs

Haskell

a061681 n = a061681_list !! n
a061681_list = iterate a182324 1  -- Reinhard Zumkeller, Apr 25 2012

Mathematica

NestList[#+First[IntegerDigits[#]]&,1,60] (* Harvey P. Dale, Aug 18 2011 *)

PARI

{ default(realprecision, 100); r=log(10); for (n=0, 1000, if (n==0, a=1, a+=a\10^(log(a)\r)); write("b061681.txt", n, " ", a) ) } \\ Harry J. Smith, Jul 26 2009

Formula

a(n+1) = A182324(a(n)), a(0) = 1.

Extensions

More terms from Naohiro Nomoto, Sep 10 2001