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A344435
a(n) = Sum_{k=1..n} (A000292(n) mod A000217(k)).
1
0, 1, 5, 4, 17, 35, 13, 35, 102, 93, 114, 148, 205, 168, 331, 435, 370, 604, 600, 539, 844, 1139, 1102, 1230, 1314, 1393, 1660, 1974, 2438, 1957, 3000, 3472, 2584, 3632, 4076, 3217, 3039, 4936, 4799, 4558, 6909, 6915, 6296, 7180, 9406, 7040, 9736, 10535, 6569, 10122, 12316, 11111, 12037, 13961
OFFSET
1,3
LINKS
FORMULA
a(n) = Sum_{k=1..n} (binomial(n+2,3) mod binomial(k+1,2)).
EXAMPLE
A000292(7) = 84 and A000217(1..7) are 1,3,6,10,15,21,28, so a(7) = (84 mod 1) + (84 mod 3) + ... + (84 mod 28) = 0+0+0+4+9+0+0 = 13.
MAPLE
f:= proc(n) local t, j;
t:= binomial(n+2, 3);
add(t mod binomial(j+1, 2), j=2..n)
end proc:
map(f, [$1..100]);
PROG
(PARI) a(n) = sum(k=1, n, binomial(n+2, 3) % binomial(k+1, 2)); \\ Michel Marcus, May 19 2021
CROSSREFS
Sequence in context: A282225 A282202 A190728 * A100791 A056883 A006747
KEYWORD
nonn
AUTHOR
J. M. Bergot and Robert Israel, May 19 2021
STATUS
approved