login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A172335 Numbers n such that n and n+17 have same sum of divisors. 1
142, 238, 418, 429, 598, 622, 2985, 3502, 16269, 22678, 23188, 27778, 38494, 46761, 48489, 62235, 74188, 98745, 110170, 120345, 129448, 151677, 187822, 190888, 194818, 205185, 223685, 235438, 246934, 249166 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

REFERENCES

M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards Applied Math. Series 55, 1964 (and various reprintings), p. 840.

J.-M. De Koninck, Ces nombres qui nous fascinent, Entry 62, p. 22, Ellipses, Paris 2008.

W. SierpiƄski, A Selection of Problems in the Theory of Numbers. Macmillan, NY, 1964, p. 110.

LINKS

Table of n, a(n) for n=1..30.

M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards, Applied Math. Series 55, Tenth Printing, 1972 [alternative scanned copy].

MAPLE

with(numtheory):for n from 1 to 250000 do; if sigma(n) = sigma(n+17) then print(n); else fi ; od;

CROSSREFS

Sequence in context: A025379 A202279 A035702 * A217531 A158135 A092230

Adjacent sequences:  A172332 A172333 A172334 * A172336 A172337 A172338

KEYWORD

nonn

AUTHOR

Michel Lagneau, Feb 01 2010

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
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 21 04:59 EDT 2019. Contains 321364 sequences. (Running on oeis4.)