A241494 - OEIS

A241494

Pyramid Top Numbers: write the decimal digits of 'n' (a nonnegative integer) and take successive absolute differences ("pyramidalization"). The number at the top of the pyramid is 'a(n)'.

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 2, 1, 0, 1, 2, 3, 4, 5, 6, 7, 3, 2, 1, 0, 1, 2, 3, 4, 5, 6, 4, 3, 2, 1, 0, 1, 2, 3, 4, 5, 5, 4, 3, 2, 1, 0, 1, 2, 3, 4, 6, 5, 4, 3, 2, 1, 0, 1, 2, 3, 7, 6, 5, 4, 3, 2, 1, 0, 1, 2, 8, 7, 6, 5

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OFFSET

0,3

COMMENTS

Through the so-called "pyramidalization" process (see A227876), a given nonnegative integer is expanded into its digits and transformed into a pyramid of successive absolute differences between digits. The present sequence is built only with the top number 'a(n)' generated from its correspondent nonnegative integer 'n'.

LINKS

Filipi R. de Oliveira, Table of n, a(n) for n = 0..9999

FORMULA

a(n)=n, if 0<=n<=9.

a(n)=|mod(n;10)-floor(n/10)|, if 10<=n<=99.

EXAMPLE

If n=1735, a(n)=0:

______0 ------>a(n)

____2_:_2

__6_:_4_:_2

1_:_7_:_3_:_5

CROSSREFS