A090068 Numbers n such that there are (presumably) seven palindromes in the Reverse and Add! trajectory of n.

6, 13, 16, 25, 31, 34, 40, 43, 44, 52, 61, 70, 77, 104, 111, 115, 145, 158, 200, 202, 203, 214, 244, 250, 257, 302, 356, 399, 401, 412, 414, 442, 455, 498, 500, 505, 511, 519, 529, 541, 554, 597, 610, 618, 626, 628, 640, 653, 656, 686, 752, 795, 797, 816, 826

Offset

1,1

Comments

For terms < 2000 each palindrome is reached from the preceding one or from the start in at most 24 steps; after the presumably last one no further palindrome is reached in 2000 steps.

Links

Table of n, a(n) for n=1..55.

Index entries for sequences related to Reverse and Add!

Example

The trajectory of 25 begins 25, 77, 154, 605, 1111, 2222, 4444, 8888, 17776, 85547, 160105, 661166, 1322332, 3654563,7309126, ...; at 7309126 it joins the (presumably) palindrome-free trajectory of A063048(7) = 10577, hence 77, 1111, 2222, 4444, 8888, 661166 and 3654563 are the seven palindromes in the trajectory of 25 and 25 is a term.

Crossrefs

Cf. A023108, A023109, A065001, A070742, A077594.

Sequence in context: A140888 A053753 A228380 * A070899 A265756 A332988

Adjacent sequences: A090065 A090066 A090067 * A090069 A090070 A090071

Keyword

nonn,base

Author

Klaus Brockhaus, Nov 20 2003

Status

approved