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A115520
Number of ordered triples (i,j,k) in range [0..n] satisfying i == j mod 2 and j == k mod 3.
1
1, 2, 5, 12, 23, 36, 61, 88, 123, 170, 227, 288, 373, 462, 565, 688, 827, 972, 1153, 1340, 1547, 1782, 2039, 2304, 2617, 2938, 3285, 3668, 4079, 4500, 4981, 5472, 5995, 6562, 7163, 7776, 8461, 9158, 9893, 10680, 11507, 12348, 13273, 14212, 15195, 16238, 17327, 18432, 19633
OFFSET
0,2
FORMULA
a(n) = binomial(n+1,3) - linear (PORC) correction term which depends on n mod 6.
CROSSREFS
Cf. A115523.
Sequence in context: A116711 A247658 A109653 * A116735 A096376 A357288
KEYWORD
nonn
AUTHOR
STATUS
approved