A008558 Repeatedly convert from decimal to octal.

9, 11, 13, 15, 17, 21, 25, 31, 37, 45, 55, 67, 103, 147, 223, 337, 521, 1011, 1763, 3343, 6417, 14421, 34125, 102515, 310163, 1135623, 4252007, 20160547, 114720043, 665476453, 4752456545, 43321135541, 502611010665, 7240574662151, 151272370273007

Offset

1,1

Links

Table of n, a(n) for n=1..35.

Mathematica

NestList[FromDigits[IntegerDigits[#, 8]]&, 9, 40] (* Harvey P. Dale, Apr 09 2012 *)

Prog

(Python)
def aupton(terms):
    alst = [9]
    for n in range(2, terms+1): alst.append(int(oct(alst[-1])[2:]))
    return alst
print(aupton(35)) # Michael S. Branicky, Sep 11 2021

Crossrefs

Cf. A007094.

Sequence in context: A065454 A334688 A248629 * A335912 A123760 A289686

Adjacent sequences: A008555 A008556 A008557 * A008559 A008560 A008561

Keyword

nonn,base

Author

sbv(AT)VNET.IBM.COM (Scott Vetter), msvetter(AT)eng.xyplex.com (Mark Vetter)

Status

approved