A065197 Solutions to A065191(n) = n.

1, 5, 90, 117, 154, 446, 3650, 4754, 8110, 69977, 74014, 401477, 432257, 545185

Offset

1,2

Links

Table of n, a(n) for n=1..14.

Mathematica

Reap[Do[pos = n; Do[pos -= k (-1)^Quotient[pos, k], {k, n, 1, -1}]; pos -= If[Mod[n, 4] < 2, 1, -1]; If[pos == n, Print[n]; Sow[n]], {n, 1, 10^4} ]][[2, 1]] (* Jean-François Alcover, Mar 02 2020, after Charlie Neder in A065191 *)

Prog

(Python)
from itertools import islice, count
def A065197gen(): # generator of terms, after Charlie Neder in A065191
    for n in count(1):
        m = n
        for k in range(n, 1, -1):
            m += k if (m//k) % 2 else -k
        if m == n:
            yield n
A065197_list = list(islice(A065197(), 10)) # Chai Wah Wu, Dec 15 2021

Crossrefs

Cf. A065191, A065192, A065193, A065194, A065195, A065196.

Sequence in context: A067258 A167424 A174591 * A300348 A336783 A300433

Adjacent sequences: A065194 A065195 A065196 * A065198 A065199 A065200

Keyword

nice,nonn,more

Author

Klaus Strassburger (strass(AT)ddfi.uni-duesseldorf.de), Oct 19 2001

Extensions

a(7)-a(9) from Charlie Neder, Feb 04 2019

a(10)-a(14) from Chai Wah Wu, Dec 15 2021

Status

approved