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A003608
Add 4, then reverse digits; start with 0.
(Formerly M3339)
5
0, 4, 8, 21, 52, 65, 96, 1, 5, 9, 31, 53, 75, 97, 101, 501, 505, 905, 909, 319, 323, 723, 727, 137, 141, 541, 545, 945, 949, 359, 363, 763, 767, 177, 181, 581, 585, 985, 989, 399, 304, 803, 708, 217, 122, 621, 526, 35, 93, 79, 38, 24, 82, 68, 27, 13, 71, 57, 16, 2, 6, 1, 5, 9, 31, 53, 75, 97, 101, 501, 505
OFFSET
0,2
COMMENTS
Enters the cycle of length 54 given in A119031 at a(7) = 1. - M. F. Hasler, Mar 15 2022
REFERENCES
J. Roberts, Lure of the Integers, Math. Assoc. America, 1992, p. 15.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
Index entries for linear recurrences with constant coefficients, signature (0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1).
FORMULA
a(n + 54) = a(n) for n >= 7.
MAPLE
rev:=proc(n) local nn, nnn: nn:=convert(n, base, 10): add(nn[nops(nn)+1-j]*10^(j-1), j=1..nops(nn)) end: a[0]:=0: for n from 1 to 70 do a[n]:=rev(a[n-1]+4) od: seq(a[n], n=0..70); # Emeric Deutsch, Mar 07 2007
MATHEMATICA
NestList[FromDigits[Reverse[IntegerDigits[#+4]]]&, 0, 70] (* Harvey P. Dale, Jan 20 2014 *)
PROG
(PARI) A003608=vector(66, i, a=if(i>1, fromdigits(Vecrev(digits(a+4))))) \\ M. F. Hasler, Mar 15 2022
(Python)
def A003608(N=66, a=0, d=4): # optional args: # terms, initial value, increment
for _ in range(N): yield a; a=int(str(a+d)[::-1])
list(A003608()) # M. F. Hasler, Mar 15 2022
CROSSREFS
All of A003608, A016081, A016082 (and possibly others) eventually reach the trajectory of 1 shown in A119031. Cf. A055198.
Sequence in context: A261031 A077921 A097076 * A248423 A319565 A129794
KEYWORD
nonn,base,easy
EXTENSIONS
Corrected by Nick Hobson, Feb 21 2007
More terms from Emeric Deutsch, Mar 07 2007
Edited by M. F. Hasler, Mar 15 2022
STATUS
approved