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A191854 First factor in happy factorization of n-th rectangular number. 6
1, 1, 2, 1, 3, 1, 7, 1, 2, 4, 3, 2, 1, 7, 1, 5, 11, 17, 1, 2, 3, 1, 6, 11, 5, 23, 1, 4, 1, 2, 11, 7, 3, 1, 15, 1, 31, 1, 2, 4, 23, 5, 8, 1, 1, 19, 7, 26, 1, 3, 1, 2, 1, 9, 23, 3, 47, 19, 1, 49, 1, 2, 5, 1, 27, 1, 10, 3, 7, 1, 2, 4, 9, 2, 1, 31, 1, 14, 3, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

a(n) = A007966(A007969(n)) = A007969(n) / A191855(n);

(a(n), A191855(n)) is a 1-happy couple;

notation: B in the Conway link.

LINKS

Table of n, a(n) for n=1..80.

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

FORMULA

a(n) * A191860(n)^2 + 1 = A191854(n) * A191861(n)^2.

CROSSREFS

Sequence in context: A034869 A205858 A053222 * A129646 A165401 A213074

Adjacent sequences:  A191851 A191852 A191853 * A191855 A191856 A191857

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Jun 18 2011

STATUS

approved

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Last modified April 18 14:05 EDT 2014. Contains 240720 sequences.