A104971 Numbers with 4 distinct digits {1,2,3,4} such that all adjacent digits(as well as first and last digits) are coprime.

1234, 1432, 2143, 2341, 3214, 3412, 4123, 4321

Offset

1,1

Links

Table of n, a(n) for n=1..8.

Mathematica

aadcpQ[k_]:=Total[Boole[CoprimeQ@@@Partition[PadRight[{}, 5, k], 2, 1]]]==4; FromDigits/@Select[Permutations[IntegerDigits[ 1234]], aadcpQ] (* Harvey P. Dale, Jan 28 2025 *)

Crossrefs

Cf. A104972, A104973.

Sequence in context: A064942 A101311 A055616 * A193492 A279204 A091332

Adjacent sequences: A104968 A104969 A104970 * A104972 A104973 A104974

Keyword

full,nonn,base,fini

Author

Zak Seidov, Mar 30 2005

Status

approved