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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.
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%I #22 Jul 01 2018 17:19:45

%S 1,2,4,8,16,17,18,19,20,22,24,26,28,30,33,36,39,42,46,50,55,60,66,72,

%T 79,86,94,103,104,105,106,107,108,109,110,111,112,113,114,115,116,117,

%U 118,119,120,121,122,123,124,125,126,127,128,129,130,131,132,133,134

%N 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.

%H Reinhard Zumkeller, <a href="/A061681/b061681.txt">Table of n, a(n) for n = 0..10000</a>

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

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

%t NestList[#+First[IntegerDigits[#]]&,1,60] (* _Harvey P. Dale_, Aug 18 2011 *)

%o (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

%o (Haskell)

%o a061681 n = a061681_list !! n

%o a061681_list = iterate a182324 1 -- _Reinhard Zumkeller_, Apr 25 2012

%K base,easy,nonn,nice,look

%O 0,2

%A _Reinhard Zumkeller_, Jun 18 2001

%E More terms from _Naohiro Nomoto_, Sep 10 2001