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Numbers having a digit 0 or 5 whose waterfall sequence does not end in 0,0,0,....
1

%I #12 Sep 26 2013 08:59:06

%S 59,195,295,395,475,495,519,533,534,536,537,538,539,547,549,566,568,

%T 572,573,574,576,577,578,579,586,588,589,591,592,593,594,596,597,598,

%U 599,665,675,685,745,759,775,795,895,935,945,957,959,975,1175,1195,1245,1275

%N Numbers having a digit 0 or 5 whose waterfall sequence does not end in 0,0,0,....

%C The "waterfall" sequence S for a given starting value S(1)>9 is defined as S(n)=d(n)*d(n-1) (n>1), where d(n) is the n-th digit of the sequence.

%C Initial values having a digit 0 or 5 are likely to end in repeating zeros, which motivates the definition of this sequence. See A210652 for further information.

%o (PARI) is_A210653(n)= setintersect(["0","5"],Set(Vec(Str(n)))) & !is_A210652(n)

%o for(n=10,1999, is_A210653(n) & print1(n", "))

%Y Cf. A210614.

%K nonn,base

%O 1,1

%A _M. F. Hasler_, Mar 27 2012