A061583
a(1) = 1, a(n) is the number obtained by replacing each digit of a(n-1) with five times its value.
Original entry on oeis.org
1, 5, 25, 1025, 501025, 250501025, 10250250501025, 501025010250250501025, 2505010250501025010250250501025, 1025025050102502505010250501025010250250501025
Offset: 1
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a:= proc(n) option remember; `if`(n=1, 1, (s-> parse(cat(
seq(parse(s[i])*5, i=1..length(s)))))(""||(a(n-1))))
end:
seq(a(n), n=1..10); # Alois P. Heinz, May 25 2018
-
NestList[FromDigits[Flatten[IntegerDigits/@(5*IntegerDigits[#])]]&,1,10] (* Harvey P. Dale, Dec 31 2013 *)
-
def A061583_first(n):
an = "1"
a061583 = []
while n > 1:
a061583.append(int(an))
newan = ""
for i in an:
newan += str(5*int(i))
an = newan
n -= 1
a061583.append(int(an))
return a061583 # John Cerkan, May 25 2018
More terms from Larry Reeves (larryr(AT)acm.org) and
Asher Auel, May 15 2001
A061584
a(1) = 1, a(n)= number obtained by replacing each digit of a(n-1) with six times its value.
Original entry on oeis.org
1, 6, 36, 1836, 6481836, 3624486481836, 1836122424483624486481836, 64818366121224122424481836122424483624486481836, 362448648183636612612122461212241224244864818366121224122424481836122424483624486481836
Offset: 1
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NestList[FromDigits[Flatten[IntegerDigits/@(6 IntegerDigits[#])]]&,1,10] (* Harvey P. Dale, Aug 26 2022 *)
-
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
More terms from Larry Reeves (larryr(AT)acm.org) and
Asher Auel, May 15 2001
A061580
a(1) = 1, a(n)= number obtained by replacing each digit of a(n-1) with four times its value.
Original entry on oeis.org
1, 4, 16, 424, 16816, 42432424, 1681612816816, 42432424483242432424, 168161281681616321281681612816816, 42432424483242432424424128483242432424483242432424
Offset: 1
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NestList[FromDigits@ Flatten@ Map[IntegerDigits, 4*IntegerDigits[#]] &, 1, 9] (* Michael De Vlieger, Feb 25 2023 *)
More terms from Larry Reeves (larryr(AT)acm.org) and
Asher Auel, May 15 2001
a(9) corrected by
N. J. A. Sloane, Jan 23 2017 at the suggestion of Carolyn Liao.
Showing 1-3 of 3 results.
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