The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A205960 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A205960

Smallest odd number with digit sum equal to n.
(history; published version)

#15 by Alois P. Heinz at Tue Sep 15 17:49:08 EDT 2020

STATUS

proposed

approved

#14 by Michel Marcus at Tue Sep 15 16:59:56 EDT 2020

STATUS

editing

proposed

#13 by Michel Marcus at Tue Sep 15 16:59:53 EDT 2020

CROSSREFS

Cf. A051885, A069532.

STATUS

proposed

editing

#12 by Chai Wah Wu at Tue Sep 15 16:19:29 EDT 2020

STATUS

editing

proposed

#11 by Chai Wah Wu at Tue Sep 15 16:19:20 EDT 2020

LINKS

<a href="/index/Rec#order_10">Index entries for linear recurrences with constant coefficients</a>, signature (1,0,0,0,0,0,0,0,10,-10).

FORMULA

From Chai Wah Wu, Sep 15 2020: (Start)

a(n) = a(n-1) + 10*a(n-9) - 10*a(n-10) for n > 18.

G.f.: x*(90*x^17 - 90*x^16 + 90*x^15 - 90*x^14 + 90*x^13 - 90*x^12 + 90*x^11 - 90*x^10 - 8*x^8 + 10*x^7 - 8*x^6 + 10*x^5 - 8*x^4 + 10*x^3 - 8*x^2 + 10*x + 1)/((x - 1)*(10*x^9 - 1)). (End)

STATUS

approved

editing

#10 by Harvey P. Dale at Mon Apr 30 14:45:06 EDT 2018

STATUS

editing

approved

#9 by Harvey P. Dale at Mon Apr 30 14:45:02 EDT 2018

MATHEMATICA

With[{ds=Table[{n, Total[IntegerDigits[n]]}, {n, 1, 600001, 2}]}, Table[ SelectFirst[ ds, #[[2]]==k&], {k, 50}]][[All, 1]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Apr 30 2018 *)

STATUS

approved

editing

#8 by Russ Cox at Sat Mar 31 10:24:06 EDT 2012

AUTHOR

_Arkadiusz Wesolowski (wesolowski(AT)aol.pl), _, Feb 02 2012

Discussion

Sat Mar 31

10:24

OEIS Server: https://oeis.org/edit/global/403

#7 by T. D. Noe at Thu Feb 02 12:37:05 EST 2012

STATUS

proposed

approved

#6 by Arkadiusz Wesolowski at Thu Feb 02 11:16:23 EST 2012

STATUS

editing

proposed