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A088504
Sum of even entries in row n of Pascal's triangle.
2
0, 0, 2, 0, 14, 20, 32, 0, 254, 492, 932, 1584, 3104, 4160, 8192, 0, 65534, 131036, 261836, 521968, 1038884, 2044440, 4029984, 7607296, 15306272, 27305280, 53360192, 77448960, 201334784, 268451840, 536870912, 0, 4294967294
OFFSET
0,3
COMMENTS
a(n) = 0 iff n = 2^k - 1.
A088560(n) = A088504(n) iff n = 2^k - 2, k>1. A088560(n) > A088504(n) iff n = 2^k - 1.
FORMULA
A088504(n) + A088560(n) = 2^n. A088504(n) - A088560(n) = A085814(n).
MATHEMATICA
f[n_] := Plus @@ Select[ Table[ Binomial[n, i], {i, 0, n}], EvenQ[ # ] & ]; Table[ f[n], {n, 0, 35}] (* Robert G. Wilson v, Nov 19 2003 *)
CROSSREFS
Cf. A048967.
Sequence in context: A287192 A219843 A064855 * A229091 A369243 A189425
KEYWORD
nonn
AUTHOR
Yuval Dekel (dekelyuval(AT)hotmail.com), Nov 18 2003
EXTENSIONS
Edited and extended by Robert G. Wilson v and Ray Chandler, Nov 19 2003
STATUS
approved