A319020 Let b_i(k) = 1 for k <= i; for n > i, b_i(n) = b_i(t(n)) + b_i(n-t(n)) where t = A063882. a(n) = 3*b_2(n)-2*n if n is even, a(n) = 3*b_4(n)-n if n is odd.

2, -1, 0, 1, 1, 0, -1, -1, 0, 1, 1, 0, 2, -1, 0, 1, -2, 0, 2, -1, 0, 1, 1, 0, 2, -1, 0, 1, -2, 0, -1, -1, 0, -2, 1, 0, -1, 2, -3, 1, 1, -3, 2, -1, 3, -2, 1, 0, -1, -1, 0, 1, -2, 0, 2, -1, 0, -2, 1, 0, -1, -1, 0, -2, 1, 0, -1, 2, 0, 1, -2, 3, -1, -1, 3, -2, 1, -3, 2, -1, 0, 1, -2, 0, 2, -4, 3, -2, 4, -3, 2, -1, 0, -2

Offset

1,1

Links

Altug Alkan, Table of n, a(n) for n = 1..9216

Prog

(PARI) t=f=g=vector(200); t[1]=t[2]=t[3]=t[4]=1; for(n=5, #t, t[n] = t[n-t[n-1]]+t[n-t[n-4]]); f[1]=f[2]=1; for(n=3, #f, f[n] = f[t[n]]+f[n-t[n]]); g[1]=g[2]=g[3]=g[4]=1; for(n=5, #g, g[n] = g[t[n]]+g[n-t[n]]); vector(200, n, if(n%2==0, 3*f[n]-2*n, 3*g[n]-n))

Crossrefs

Cf. A063882, A317686, A317754, A317854.

Sequence in context: A074871 A182641 A337939 * A099200 A358351 A093578

Adjacent sequences: A319017 A319018 A319019 * A319021 A319022 A319023

Keyword

sign,look

Author

Altug Alkan, Sep 08 2018

Status

approved