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A179612 Sums of pairs of betrothed (or quasi-amicable) numbers. 0
123, 335, 2975, 3223, 4319, 11903, 25479, 30239, 138239, 393119, 416639, 508895, 773759, 861839, 1071359, 1391039, 1645055, 2903039, 2413151, 2298239, 2903039, 2515199, 2557439, 2757887, 2695679, 3856895, 4147199, 4717439, 4245695, 4561919, 5391359, 5322239 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

This is to A161005 sums of pairs of amicable numbers as betrothed (or quasi-amicable) numbers A005276 are to A063990 amicable numbers. The subsequence of primes begins: 11903, 138239, 1071359.

LINKS

Table of n, a(n) for n=1..32.

FORMULA

a(n) = A003502(n) + A003503(n). {(j + k) such that sigma(j)=sigma(k)=j+k+1, where sigma=A000203}.

EXAMPLE

a(1) = 48 + 75 = 123 = 3 * 41.

a(2) = 140 + 195 = 335 = 5 * 67.

a(6) = 5775 + 6128 = 11903 is the smallest prime in these pair-sums.

CROSSREFS

Cf. A000203, A003502, A003503, A005276, A063990, A161005.

Sequence in context: A216382 A269751 A235133 * A091331 A248556 A031689

Adjacent sequences:  A179609 A179610 A179611 * A179613 A179614 A179615

KEYWORD

nonn

AUTHOR

Jonathan Vos Post, Jan 08 2011

EXTENSIONS

More terms from Amiram Eldar, Jan 27 2019

STATUS

approved

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Last modified October 23 12:19 EDT 2019. Contains 328345 sequences. (Running on oeis4.)