A061584 a(1) = 1, a(n)= number obtained by replacing each digit of a(n-1) with six times its value.

1, 6, 36, 1836, 6481836, 3624486481836, 1836122424483624486481836, 64818366121224122424481836122424483624486481836, 362448648183636612612122461212241224244864818366121224122424481836122424483624486481836

Offset: 1

Author

Amarnath Murthy, May 13 2001

Keywords

• nonn
• base
• easy

Comments

a(n) contains all of a(n-1) as its least significant digits.

Links

• John Cerkan, Table of n, a(n) for n = 1..13

Crossrefs

Cf. A061581, A061582, A061583, A061585, A061586, A061587, A061533.

Programs

Mathematica

NestList[FromDigits[Flatten[IntegerDigits/@(6 IntegerDigits[#])]]&,1,10] (* Harvey P. Dale, Aug 26 2022 *)

Python

def A061584_first(n):
    an = "1"
    a061584 = []
    while n > 1:
        a061584.append(int(an))
        newan = ""
        for i in an:
            newan += str(6*int(i))
        an = newan
        n -= 1
    a061584.append(int(an))
    return a061584 # John Cerkan, May 25 2018

Extensions

More terms from Larry Reeves (larryr(AT)acm.org) and Asher Auel, May 15 2001