A191914 Smallest number m greater than n such that the happy couples of m and n have a member in common.

2, 3, 5, 6, 7, 8, 10, 12, 12, 11, 13, 15, 17, 18, 20, 20, 19, 22, 23, 24, 28, 32, 26, 28, 30, 27, 29, 35, 31, 35, 37, 34, 39, 38, 42, 42, 41, 40, 52, 46, 43, 48, 47, 52, 55, 54, 50, 56, 56, 51, 53, 60, 58, 62, 70, 63, 69, 59, 61, 68, 65, 66, 72, 72, 67, 86

Offset: 1

Author

Reinhard Zumkeller, Jun 19 2011

Keywords

• nonn

Comments

The intersection of {A007966(n),A007967(n)} and {A007966(a(n)),A007967(a(n))} is not empty, but the intersection of {A007966(n),A007967(n)} and {A007966(m),A007967(m)} is empty for n

Examples

			Let hc(n) = (A007966(n),A007967(n)),
n=6, a(6) =  8: hc(6) = (2,3) and hc(8)  = (2,4)  with common 2,
n=7, a(7) = 10: hc(7) = (7,1) and hc(10) = (1,10) with common 1,
n=8, a(8) = 12: hc(8) = (2,4) and hc(12) = (3,4)  with common 4,
n=9, a(9) = 12: hc(9) = (3,3) and hc(12) = (3,4)  with common 3.
		

Links

• J. H. Conway, On Happy Factorizations, J. Integer Sequences, Vol. 1, 1998, #1.

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