A070042 At these values of n the first, 2nd, 3rd, 4th and 5th cyclotomic polynomials all give prime numbers.

1068630, 1441590, 1867950, 3429300, 4084230, 5651730, 6322890, 6770610, 7158630, 7804830, 9437760, 9624270, 13625850, 23194860, 25848840, 26588520, 28714950, 29451840, 32984430, 33650580, 36500910, 38177130, 42856590

Offset

1,1

Links

Table of n, a(n) for n=1..23.

Formula

C1(n)=n-1, C2(n)=n+1, C3(n)=1+n+n^2, C4(n)=1+n^2 and C5(n)=1+n+n^2+n^3+n^4 are all primes.

Example

n=1068630: gives quintet of primes of first, 2nd, 3rd, 4th and 5th cyclotomic polynomials: {1068629, 1068631, 1141971145531, 1141970076901, 1304096876879617162402531}.

Crossrefs

Cf. A070155-A070157, A000068, A006313-A006316, A056993-A056995, A005574, A057465, A057002, A070020, A070025.

Sequence in context: A193054 A160687 A342328 * A258061 A187125 A237972

Adjacent sequences: A070039 A070040 A070041 * A070043 A070044 A070045

Keyword

easy,nonn

Author

Labos Elemer, May 07 2002

Extensions

More terms from Don Reble, May 11 2002

Status

approved