cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A187871 a(1)=1; for n > 1, a(n) is the smallest number that is formed by arranging the decimal numbers "1", "2", ..., "n" in some order so that the sum of every pair of adjacent numbers "i" "j" is prime.

Table of values

n a(n)
1 1
2 12
3 123
4 1234
5 14325
6 143256
7 1234765
8 12347658
9 123476589
10 10123476589
11 1103211658947
12 101121123476589
13 11013432111276589
14 1011211231458941367
15 110134151432111276589
16 10112112151431613476589
17 1101316151417121123476589
18 101121118131615141723476589

List of values

[1, 12, 123, 1234, 14325, 143256, 1234765, 12347658, 123476589, 10123476589, 1103211658947, 101121123476589, 11013432111276589, 1011211231458941367, 110134151432111276589, 10112112151431613476589, 1101316151417121123476589, 101121118131615141723476589]

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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