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A088488
a(n) = Sum_{k=1..8} floor(A254876(n,k)/A254876(n-1,k)), where A254876(n,k) = n! / (Product_{m=(n-floor((2n)/(3^k))) .. (n-floor((n)/(3^k)))} m).
5
8, 17, 22, 26, 40, 43, 49, 66, 65, 69, 87, 87, 68, 109, 108, 109, 137, 130, 130, 157, 153, 133, 180, 174, 171, 211, 196, 191, 227, 218, 186, 250, 240, 232, 280, 262, 253, 298, 285, 164, 319, 304, 292, 350, 327, 313, 367, 349, 292, 390, 371, 354, 426, 393, 375
OFFSET
2,1
LINKS
FORMULA
a(n) = Sum_{k=1..8} floor(A254876(n,k)/A254876(n-1,k)), where A254876(n,k) = n! / (Product_{m=(n-floor((2n)/(3^k))) .. (n-floor((n)/(3^k)))} m).
MATHEMATICA
p[n_, k_]=n!/Product[i, {i, n-Floor[2*n/3^k], n-Floor[n/3^k]}]
f[n_]=Sum[Floor[p[n, k]/p[n-1, k]], {k, 1, 8}]
at=Table[f[n], {n, 2, 200}]
PROG
(PARI)
A088488(n) = sum(k=1, 8, (A254876bi(n, k)\A254876bi(n-1, k)));
A254876bi(n, k) = n! / prod(i=(n-((2*n)\(3^k))), (n-(n\(3^k))), i);
for(n=2, 10000, write("b088488.txt", n, " ", A088488(n)));
(Scheme)
(define (A088488 n) (add (lambda (k) (floor->exact (/ (A254876bi n k) (A254876bi (- n 1) k)))) 1 8))
;; The following function implements sum_{i=lowlim..uplim} intfun(i)
(define (add intfun lowlim uplim) (let sumloop ((i lowlim) (res 0)) (cond ((> i uplim) res) (else (sumloop (1+ i) (+ res (intfun i)))))))
CROSSREFS
Sequence in context: A271626 A023700 A026231 * A031458 A044991 A063594
KEYWORD
nonn,less
AUTHOR
Roger L. Bagula, Nov 09 2003
EXTENSIONS
Edited by Antti Karttunen, Feb 09 2015
STATUS
approved