login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A111908 Numbers that are not the sum of a prime and a nonzero triangular number. 1
1, 2, 7, 36, 61, 105, 171, 210, 211, 216, 325, 351, 406, 528, 561, 630, 741, 780, 990, 1081, 1176, 1275, 1596, 1711, 1830, 1953, 2016, 2145, 2346, 2628, 2775, 3003, 3081, 3240, 3321, 3655, 3741, 3916, 4278, 4371, 4465, 4560, 4851, 5253, 5460, 5565, 5886 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Can anybody prove or disprove a(n) = O(n^c) for some constant c?

Jonathan Vos Post has observed that every term in A076768 also occurs in this sequence.

LINKS

Donovan Johnson, Table of n, a(n) for n = 1..10000

EXAMPLE

7 = 1+6 = 2+5 = 3+4; 7 is in the sequence because there is no sum where the first element is a prime and the second one a triangular number.

CROSSREFS

Cf. A064233, A000217, A076768, A020756, A072386, A014089, A014090, A000404, A001481, A002654, A100570, A101181.

Sequence in context: A247240 A266356 A196857 * A060814 A192816 A302895

Adjacent sequences:  A111905 A111906 A111907 * A111909 A111910 A111911

KEYWORD

nonn

AUTHOR

Stefan Steinerberger, Nov 25 2005

EXTENSIONS

a(47) and offset corrected by Donovan Johnson, Feb 09 2013

STATUS

approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified June 26 20:07 EDT 2022. Contains 354885 sequences. (Running on oeis4.)