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%I #8 Jun 03 2021 15:24:17
%S 2,3,4,5,6,7,8,9,10,11,12,14,16,18,20,23,27,32,38,44,50,56,62,69,76,
%T 83,90,97,104,111,118,125,133,141,149,157,165,173,181,189,197,205,214,
%U 224,236,249,263,278,294,311,328,346,364,382,401,420,440,460,480,500,520
%N a(1) = 2; a(n) = a(n-1) + (number of times the digit 2 has appeared in the sequence so far).
%H Harvey P. Dale, <a href="/A130225/b130225.txt">Table of n, a(n) for n = 1..1000</a>
%p A130225 := proc(n)
%p option remember;
%p if n = 1 then
%p 2;
%p else
%p a := procname(n-1) ;
%p for j from 1 to n-1 do
%p for d in convert(procname(j),base,10) do
%p if d = 2 then
%p a := a+1 ;
%p end if;
%p end do:
%p end do:
%p a ;
%p end if;
%p end proc:
%p seq(A130225(n),n=1..80) ; # _R. J. Mathar_, Aug 06 2016
%t nxt[{t_,a_}]:=Module[{k=a+t},{t+DigitCount[k,10,2],k}]; NestList[nxt,{1,2},60][[All,2]] (* _Harvey P. Dale_, Jun 03 2021 *)
%K base,easy,nonn
%O 1,1
%A _Eric Angelini_, Aug 05 2007
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