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Add 4, then reverse digits; start with 3.
5

%I #24 Mar 16 2022 02:59:58

%S 3,7,11,51,55,95,99,301,503,705,907,119,321,523,725,927,139,341,543,

%T 745,947,159,361,563,765,967,179,381,583,785,987,199,302,603,706,17,

%U 12,61,56,6,1,5,9,31,53,75,97,101,501,505,905,909,319,323,723,727,137,141,541

%N Add 4, then reverse digits; start with 3.

%C At 41st term, 1, the sequence joins the trajectory for a(1)=1, A119031. Cycle of length 54. - _Zak Seidov_, May 09 2006. (Corrected by _N. J. A. Sloane_, Aug 02 2009.)

%p rev:=proc(n) local nn: nn:=convert(n,base,10): add(nn[j]*10^(nops(nn)-j),j= 1..nops(nn)) end proc: a[1]:=3: for n from 2 to 60 do a[n]:=rev(4+a[n-1]) end do: seq(a[n],n=1..60); # _Emeric Deutsch_, Aug 26 2007

%t NestList[FromDigits[Reverse[IntegerDigits[#+4]]]&,3,60] (* _Harvey P. Dale_, Oct 01 2015 *)

%o (PARI) a=26; A016081=vector(99, i, a=fromdigits(Vecrev(digits(a+4)))) \\ _M. F. Hasler_, Mar 15 2022

%o (Python)

%o def A016081(N=99, a=3, d=4): # optional args: # terms, initial value, increment

%o for _ in range(N): yield a; a=int(str(a+d)[::-1])

%o list(A016081()) # _M. F. Hasler_, Mar 15 2022

%Y All of A003608, A016081, A016082 (and possibly others) eventually reach the trajectory of 1 shown in A119031. Cf. A055198.

%K nonn,base

%O 1,1

%A _Robert G. Wilson v_

%E Corrected and extended by _Franklin T. Adams-Watters_, Mar 30 2006

%E Edited by _N. J. A. Sloane_ at the suggestion of _Andrew S. Plewe_, Aug 23 2007

%E Name edited by _M. F. Hasler_, Mar 15 2022