A210653 Numbers having a digit 0 or 5 whose waterfall sequence does not end in 0,0,0,....

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

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

Table of n, a(n) for n=1..52.

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

Cf. A210614.

Sequence in context: A142857 A142064 A114353 * A325081 A142092 A142215

Adjacent sequences: A210650 A210651 A210652 * A210654 A210655 A210656

Keyword

nonn,base

Author

M. F. Hasler, Mar 27 2012

Status

approved