login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A262873 Predestined numbers A262743 in which every term is generated by at least one pair of products where all (and only those) first product's factor's digits are, in reverse order, the same as those of the second two factors. 3
504, 756, 806, 868, 1008, 1148, 1176, 1209, 1472, 1475, 1512, 1638, 1708, 2016, 2184, 2208, 2418, 2548, 2730, 2772, 2924, 3024, 3388, 4416 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

In this sequence, the position of the multiplication sign in the reversed order is irrelevant, so, e.g., 11088 (48*231 and 132*84), 1176 (4*294 and 49*24) and 2548 (4*637 and 7*364) are in the sequence.

REFERENCES

Francesco Di Matteo, Sequenze ludiche, Game Edizioni (2015), page 34.

LINKS

Francesco Di Matteo, Table of n, a(n) for n = 1..132

Algebra.com, Question 265287

A. Marchini and F. Di Matteo, All the first 132 terms calculated

Math Forum at Drexel, Reversing the Digits

EXAMPLE

504  = 12*42 = 24*21;

756  = 12*63 = 36*21;

806  = 13*62 = 26*31;

868  = 4*217 = 7*124;

1008 = 12*84 = 48*21;

1148 = 14*82 = 28*41;

1176 = 4*294 = 49*24, etc.

CROSSREFS

Subsequence of A262743.

Cf. A228164 (contains only symmetrical digits' factors)

Sequence in context: A066525 A043304 A045212 * A228164 A060666 A335654

Adjacent sequences:  A262870 A262871 A262872 * A262874 A262875 A262876

KEYWORD

nonn,base

AUTHOR

Francesco Di Matteo, Oct 03 2015

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified June 26 18:18 EDT 2022. Contains 354885 sequences. (Running on oeis4.)