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A281190 Concatenation of the reversed digits of numbers from 1 to n, mod n. 1
0, 0, 0, 2, 0, 0, 5, 6, 0, 1, 6, 9, 3, 1, 6, 9, 5, 9, 1, 2, 18, 6, 12, 18, 2, 6, 18, 26, 7, 3, 20, 27, 6, 3, 28, 27, 7, 19, 12, 24, 4, 24, 12, 28, 9, 8, 42, 12, 22, 5, 3, 45, 41, 45, 50, 45, 45, 23, 16, 6, 6, 54, 27, 30, 61, 6, 37, 30, 21, 67, 47, 63, 52, 67, 57, 19, 28, 15, 58, 28, 72, 22, 56, 24, 83, 34, 3, 72, 72, 9, 85, 69, 57 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

Note that leading zeros are not omitted when numbers are reversed. - N. J. A. Sloane, Jan 23 2017

LINKS

Indranil Ghosh, Table of n, a(n) for n = 1..20008

FORMULA

a(n) = A138957(n) mod n.

EXAMPLE

a(13) = A138957(13) mod 13 == 12345678901112131 mod 13 == 3.

MATHEMATICA

f[n_] := Mod[ Fold[#1*10^IntegerLength@#2 + FromDigits@ Reverse@ IntegerDigits@#2 &, 0, Range@ n], n]; Array[f, 105]

PROG

(Python)

def A281190(n):

....s=""

....for i in range(1, n+1):

........s+=str(i)[::-1]

....return int(s)%n # Indranil Ghosh, Jan 28 2017

(PARI) a(n) = my(s = ""); for (k=1, n, sk = digits(k); forstep (j=#sk, 1, -1, s = concat(s, sk[j]))); eval(s) % n; \\ Michel Marcus, Jan 28 2017

CROSSREFS

Cf. A029503, A095221, A114795, A138957, A281066.

Sequence in context: A278177 A095221 A078112 * A275619 A249132 A128711

Adjacent sequences:  A281187 A281188 A281189 * A281191 A281192 A281193

KEYWORD

base,easy,nonn

AUTHOR

Robert G. Wilson v, Jan 16 2017

STATUS

approved

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Last modified October 27 23:46 EDT 2021. Contains 348305 sequences. (Running on oeis4.)