A174928 Partial sums of A174927.

1, 65, 66, 130, 131, 195, 196, 260, 261, 325, 326, 390, 391, 455, 456, 520, 521, 585, 586, 650, 651, 715, 716, 780, 781, 845, 846, 910, 911, 975, 976, 1040, 1041, 1105, 1106, 1170, 1171, 1235, 1236, 1300, 1301, 1365, 1366, 1430, 1431, 1495, 1496, 1560

Offset

0,2

Comments

First differences of A174929.

Links

Table of n, a(n) for n=0..47.

Index entries for linear recurrences with constant coefficients, signature (1, 1, -1).

Formula

a(n) = (67+130*n-63*(-1)^n)/4.

a(n) = a(n-2)+65 for n > 1; a(0) = 1, a(1) = 65.

a(n) = ((n+1) mod 2) + 65*floor((n+1)/2).

G.f.: (1+64*x)/((1-x)^2*(1+x)).

Prog

(Magma) T:=&cat[ [1, 64]: n in [0..23] ]; [ n eq 1 select T[1] else Self(n-1)+T[n]: n in [1..#T] ];
[ n le 2 select 64*n-63 else Self(n-2)+65: n in [1..48] ];

Crossrefs

Cf. A174927 (repeat 1, 64), A174929.

Sequence in context: A043625 A296877 A044875 * A355313 A354474 A081647

Adjacent sequences: A174925 A174926 A174927 * A174929 A174930 A174931

Keyword

nonn

Author

Klaus Brockhaus, Apr 02 2010

Status

approved