A067079 Right digitorial function Rd(n) = abcd...*bcd...*cd...*d...*..., for n = abcd... in decimal notation.

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 11, 24, 39, 56, 75, 96, 119, 144, 171, 0, 21, 44, 69, 96, 125, 156, 189, 224, 261, 0, 31, 64, 99, 136, 175, 216, 259, 304, 351, 0, 41, 84, 129, 176, 225, 276, 329, 384, 441, 0, 51, 104, 159, 216, 275, 336, 399, 464, 531, 0, 61, 124, 189

Offset

0,3

Comments

Rd(abcd) = abcd*bcd*cd*d, etc.

Links

Reinhard Zumkeller, Table of n, a(n) for n = 0..10000

Formula

a(n) = Product_{k=1..length(n)} (n-10^k*floor(n/10^k)). - Vladeta Jovovic, Jan 08 2002

a(n) = 0 iff n == 0 (mod 10). - M. F. Hasler, Feb 25 2019

Example

Rd(256) = 256*56*6 = 86016.

Maple

seq(mul(n mod 10^k, k=1..ilog10(n)+1), n=1..63); # Paolo P. Lava, Feb 21 2019

Mathematica

Table[d = IntegerDigits[n]; rd = 1; While[ Length[d] > 0, rd = rd*FromDigits[d]; d = Drop[d, 1]]; rd, {n, 1, 75} ]
Join[{0}, Table[Times@@FromDigits/@NestList[Rest[#]&, IntegerDigits[n], IntegerLength[ n]-1], {n, 70}]] (* Harvey P. Dale, Nov 29 2014 *)

Prog

(Haskell)
import Data.List (tails)
a067079 = product . map read . init . tails . show :: Integer -> Integer
-- Reinhard Zumkeller, Apr 23 2013
(PARI) A067079(n)=prod(k=1, logint(n+!n, 10)+1, n-n\10^k*10^k) \\ M. F. Hasler, Feb 25 2019

Crossrefs

Cf. A067080.

Sequence in context: A349422 A056967 A321243 * A080434 A062567 A069554

Adjacent sequences: A067076 A067077 A067078 * A067080 A067081 A067082

Keyword

base,nonn,nice,look

Author

Amarnath Murthy, Jan 05 2002

Extensions

More terms from Robert G. Wilson v, Jan 07 2002

Status

approved