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A257805
Partial sums of A257259: a(0) = 1; for n >= 1, a(n) = A257259(n) + a(n-1).
3
1, 0, 0, -1, -2, -5, -6, -12, -20, -30, -37, -41, -39, -37, -51, -141, -459, -1355, -3521, -8212, -17510, -34685, -64692, -114953, -196617, -326254, -527227, -828432, -1254932, -1800115, -2361626, -2613748, -1777205, 1765725, 11078200, 31587185, 72445272, 148564309, 283768148, 516004565, 906713910, 1559424960, 2660917133, 4581930804, 8140743021, 15311144248, 31111188060, 68512065476
OFFSET
0,5
FORMULA
a(0) = 1; for n >= 1, a(n) = A257259(n) + A257805(n-1).
Other identities. For all n >= 0:
a(n) = -A257806(A218600(n+1)).
PROG
(Scheme, with memoization-macro definec)
(definec (A257805 n) (if (zero? n) 1 (+ (A257259 n) (A257805 (- n 1)))))
;; Alternative implementation:
(define (A257805 n) (- (A257806 (A218600 (+ 1 n)))))
CROSSREFS
Cf. also A218542, A218543 and A218789.
Sequence in context: A058601 A108365 A064765 * A082552 A243798 A057683
KEYWORD
sign
AUTHOR
Antti Karttunen, May 13 2015
STATUS
approved