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A163139 First differences of A163128. 0
1, 1, 1, 1, 10, 10, 10, 10, 10, 10, 10, 10, 10, 1, 10, 10, 10, 10, 10, 10, 10, 10, 10, 1, 10, 10, 10, 10, 10, 10, 10, 10, 10, 1, 10, 10, 10, 10, 10, 10, 10, 10, 10, 1, 10, 10, 10, 10, 10, 10, 10, 10, 10, 1, 10, 10, 10, 10, 10, 10, 10, 10, 10, 1, 10, 10, 10, 10, 10, 10, 10, 10, 10, 1, 10 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

First differences of self numbers, minus 1.

LINKS

Table of n, a(n) for n=1..75.

FORMULA

a(n) = A163128(n+1) - A163128(n) = A003052(n+1) - A003052(n) - 1.

EXAMPLE

a(6) = 24 - 14 = 10.

MAPLE

A007953 := proc(n) add(d, d=convert(n, base, 10)) ; end:

isA003052 := proc(n) for k from 1 to n do if k+A007953(k) = n then RETURN(false) ; fi; od: true; end:

A003052 := proc(n) option remember; if n = 1 then 1; else for a from procname(n-1)+1 do if isA003052(a) then RETURN(a) ; fi; od: fi; end:

for n from 1 to 100 do printf("%d, ", A003052(n+1)-A003052(n)-1) ; od: # R. J. Mathar, Jul 31 2009

CROSSREFS

Cf. A003052, A163128.

Sequence in context: A239051 A131722 A072803 * A269352 A010692 A109751

Adjacent sequences:  A163136 A163137 A163138 * A163140 A163141 A163142

KEYWORD

nonn,base

AUTHOR

Juri-Stepan Gerasimov, Jul 21 2009

EXTENSIONS

Missing 10's inserted by R. J. Mathar, Jul 31 2009

STATUS

approved

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Last modified March 20 15:43 EDT 2019. Contains 321345 sequences. (Running on oeis4.)