

A003503


The larger of a betrothed pair.


6



75, 195, 1925, 1648, 2295, 6128, 16587, 20735, 75495, 206504, 219975, 309135, 507759, 549219, 544784, 817479, 1057595, 1902215, 1331967, 1159095, 1763019, 1341495, 1348935, 1524831, 1459143, 2576945, 2226014, 2681019, 2142945, 2421704, 3220119, 3123735
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OFFSET

1,1


COMMENTS

It has been shown that (1) all known betrothed pairs are of opposite parity and (2) if a and b are a betrothed pair, and if a < b are of the same parity, then a > 10^10. See the reference for the Hagis & Lord paper. Can it be shown that all betrothed pairs are of opposite parity?  Harvey P. Dale, Apr 07 2013


REFERENCES

R. K. Guy, Unsolved Problems in Number Theory, B5.


LINKS

Donovan Johnson, Table of n, a(n) for n = 1..1000
P. Hagis and G. Lord, Quasiamicable numbers, Math. Comp. 31 (1977), 608611.


CROSSREFS

Cf. A003502, A005276.
Sequence in context: A228306 A044407 A044788 * A201916 A098230 A258056
Adjacent sequences: A003500 A003501 A003502 * A003504 A003505 A003506


KEYWORD

nonn,nice,changed


AUTHOR

Robert G. Wilson v


EXTENSIONS

Computed by Fred W. Helenius (fredh(AT)ix.netcom.com)
Extended by T. D. Noe, Dec 29 2011


STATUS

approved



