A069565 a(0) = 1, a(n) = k*a(n-1) + 1 is a multiple of n-th prime. If no such number exists then a(n) = 0 and a(n+1) = k*a(n-1) + 1 is a multiple of (n+1)-th prime; i.e., a(r) = smallest multiple of the r-th prime = k* a(s) + 1 where a(s) is the last nonzero term.

1, 2, 3, 10, 21, 22, 221, 0, 2432, 9729, 19459, 136214, 1770783, 10624699, 446237359, 8478509822, 195005725907, 5655166051304, 90482656820865, 2171583763700761, 86863350548030441, 1216086907672426175

Offset

0,2

Links

Table of n, a(n) for n=0..21.

Example

a(6) = 221 = 13*17. Hence there exists no number of the form k*221 + 1 which can be divisible by 17. Hence a(7) = 0 and a(8) = 2432 = 11*221 + 1 is divisible by 19.

Crossrefs

Cf. A069563, A069563, A069564.

Sequence in context: A352394 A225477 A079161 * A139694 A064497 A161522

Adjacent sequences: A069562 A069563 A069564 * A069566 A069567 A069568

Keyword

nonn

Author

Amarnath Murthy, Mar 23 2002

Extensions

More terms from Robert G. Wilson v, Mar 27 2002

Status

approved