A323602 Smallest b > 1 not already in the sequence such that b^(c-1) == 1 (mod c), i.e., c is a base-b Fermat pseudoprime, where c is the n-th composite number (A002808).

5, 7, 9, 8, 11, 13, 15, 4, 17, 19, 21, 20, 23, 25, 18, 27, 26, 29, 31, 33, 10, 35, 6, 37, 39, 14, 41, 43, 45, 19, 47, 49, 30, 51, 16, 53, 55, 34, 57, 56, 59, 61, 63, 62, 65, 12, 67, 69, 22, 71, 73, 75, 74, 77, 76, 79, 81, 80, 83, 85, 38, 87, 28, 89, 91, 3, 93

Offset

1,1

Comments

Is this a permutation of the positive integers > 1?

Links

Table of n, a(n) for n=1..67.

Prog

(PARI) my(v=vector(1)); forcomposite(c=1, 50, my(b=2); while(Mod(b, c)^(c-1)!=1, b++; if(Mod(b, c)^(c-1)==1, for(k=1, #v, if(b==v[k], b++)))); v=concat(v, b); print1(v[#v], ", "))

Crossrefs

Cf. A002808, A242742, A259234, A323603.

Sequence in context: A109352 A228578 A242742 * A164029 A364681 A143730

Adjacent sequences: A323599 A323600 A323601 * A323603 A323604 A323605

Keyword

nonn

Author

Felix Fröhlich, Jan 19 2019

Status

approved