|
|
A210653
|
|
Numbers having a digit 0 or 5 whose waterfall sequence does not end in 0,0,0,....
|
|
1
|
|
|
59, 195, 295, 395, 475, 495, 519, 533, 534, 536, 537, 538, 539, 547, 549, 566, 568, 572, 573, 574, 576, 577, 578, 579, 586, 588, 589, 591, 592, 593, 594, 596, 597, 598, 599, 665, 675, 685, 745, 759, 775, 795, 895, 935, 945, 957, 959, 975, 1175, 1195, 1245, 1275
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
COMMENTS
|
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.
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.
|
|
LINKS
|
|
|
PROG
|
(PARI) is_A210653(n)= setintersect(["0", "5"], Set(Vec(Str(n)))) & !is_A210652(n)
for(n=10, 1999, is_A210653(n) & print1(n", "))
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn,base
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|