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A088117 Let the decimal expansion of n be abcd...; then a(n) = {a*bcd... + b*acd... + c*abc... + ...} + {ab*cd} + ... . That is, a(n)=sum over all the digit strings of the product (number obtained by deleting a digit string) * (deleted digit string). 3
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 0, 3, 6, 9, 12, 15, 18, 21, 24, 27, 0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,12

COMMENTS

Each product is used only once.

a(n) = 0 for 0<=n<=9.

The initial 100 terms match those of A007954.

LINKS

Table of n, a(n) for n=0..59.

EXAMPLE

a(1234) = (234 + 2*134 + 3*124 + 4*123) + (12*34 + 23*14) = 1774.

a(12345) = 2345 + 2*1345 + 3*1245 + 4*1235 + 5*1234 + ( 12*345 + 23*145 + 34*125 + 45*123).

CROSSREFS

Cf. A007954, A088116.

Sequence in context: A141022 A004720 A088118 * A257850 A171765 A080464

Adjacent sequences:  A088114 A088115 A088116 * A088118 A088119 A088120

KEYWORD

base,easy,nonn

AUTHOR

Amarnath Murthy, Sep 25 2003

EXTENSIONS

Edited by N. J. A. Sloane at the suggestion of Andrew Plewe, Jul 14 2007

STATUS

approved

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Last modified May 27 07:41 EDT 2017. Contains 287198 sequences.