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A078501
a(n) = sum(k=1,n^2, A078446(k)).
0
1, 7, 26, 78, 211, 537, 1312, 3112, 7217, 16443, 36934, 82002, 180319, 393325, 852092, 1835148, 3932317, 8388783, 17825986, 37748950, 79692011, 167772417, 352321816, 738197808, 1543504201, 3221225827, 6710886782, 13958644122
OFFSET
1,2
FORMULA
a(n) = 2*(n-2)*2^n + n*(n+1)/2 + 4
G.f.: x*(1-4*x^2+4*x^3)/((2*x-1)^2 * (1-x)^3) [From Maksym Voznyy (voznyy(AT)mail.ru), Jul 27 2009]
PROG
(PARI) a(n)=2*(n-2)*2^n +n*(n+1)/2+4
CROSSREFS
Sequence in context: A180669 A027964 A183957 * A247557 A027937 A135026
KEYWORD
nonn
AUTHOR
Benoit Cloitre, Jan 04 2003
EXTENSIONS
G.f. proposed by Maksym Voznyy checked and corrected by R. J. Mathar, Sep 16 2009.
STATUS
approved