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A214132 Lesser term of smallest primitive friendly pair such that both terms are divisible by the n-th prime p and coprime to the primes below p. 2
6, 135, 14105, 15506071, 432712085377, 1890948943, 14783271043, 45847, 211838579, 147560225903398137982300169126840969637180767467, 12060713581457342807125295910808091355523729 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

For n>2, instances are known up to 11 (p=31).

By definition, gcd(a(n), A002110(n-1)) = 1. - Michel Marcus, Jan 19 2014

LINKS

Table of n, a(n) for n=1..11.

Achim Flammenkamp, The Multiply Perfect Numbers Page (for p = 13, 17, 19)

Michel Marcus, Table A214132 and A214133 for n = 1..11

EXAMPLE

For n=1, the perfect numbers 6=2*3 and 28=2^2*7 (A214133) are primitive friendly.

For n=2, 135=3^3*5 and 819=3^2*7*13 (A214133) are primitive friendly.

CROSSREFS

Cf. A214133. Subset of sequence A096366.

Sequence in context: A333005 A013299 A013295 * A196703 A196852 A196946

Adjacent sequences:  A214129 A214130 A214131 * A214133 A214134 A214135

KEYWORD

hard,more,nonn

AUTHOR

Michel Marcus, Jul 05 2012

STATUS

approved

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Last modified September 17 06:16 EDT 2021. Contains 347478 sequences. (Running on oeis4.)