This site is supported by donations to The OEIS Foundation.

 Annual appeal: Please make a donation to keep the OEIS running! Over 6000 articles have referenced us, often saying "we discovered this result with the help of the OEIS". Other ways to donate

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A138953 Sum of numbers from all substrings of n. 3
 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 8, 9, 10, 11, 12, 13, 14, 15 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,12 LINKS Zak Seidov and Christian N. K. Anderson, Table of n, a(n) for n = 0..10000 (first 1000 terms from Zak Seidov) FORMULA a(n) = A071980(n) - n. [R. J. Mathar, Jul 06 2009] Note: Mathar's formula works for numbers with 1, 2 or 3 digits, but thereafter only for numbers whose internal digits are zeros. [Christian N. K. Anderson, May 13 2013] EXAMPLE One-digit numbers have no substring, hence a(0..9)=0; a(10)  = 1+0 = 1, a(123) = 1+2+3+12+23 = 41, a(150) = 1+5+0+15+50 = 71. MATHEMATICA Table[id=IntegerDigits[n]; Total[Flatten[Table[FromDigits/@ Partition[id, k, 1], {k, Length[id]-1}]]], {n, 0, 150}] CROSSREFS Cf. A093882. Sequence in context: A103693 A117230 A093882 * A053392 A114925 A043270 Adjacent sequences:  A138950 A138951 A138952 * A138954 A138955 A138956 KEYWORD nonn,base AUTHOR Zak Seidov, Apr 04 2008 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.