The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
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!)
A262513 Numbers where A049820 takes a unique value; numbers n for which A060990(A049820(n)) = 1. 4
5, 6, 7, 8, 11, 14, 17, 18, 20, 22, 23, 24, 27, 32, 34, 35, 40, 43, 46, 47, 50, 51, 57, 58, 61, 65, 72, 73, 77, 79, 81, 84, 86, 87, 88, 92, 93, 94, 96, 97, 98, 99, 101, 102, 103, 105, 107, 114, 116, 119, 120, 123, 125, 130, 135, 137, 143, 151, 154, 155, 158, 160, 163, 164, 173, 175, 177, 179, 184, 187, 191, 193, 194, 197, 198, 200, 203, 204, 206, 209, 210, 212 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Sequence A262512 sorted into ascending order.
Numbers n such that there is no other number k for which A049820(k) = A049820(n).
LINKS
MATHEMATICA
lim = 212; s = Table[n - DivisorSigma[0, n], {n, 2 lim + 3}]; t = Length@ Position[s, #] & /@ Range[0, lim]; Position[t[[# + 1]] & /@ Take[s, lim], 1] // Flatten (* Michael De Vlieger, Sep 29 2015, after Wesley Ivan Hurt at A049820 *)
PROG
(Scheme, with Antti Karttunen's IntSeq-library)
(define A262513 (MATCHING-POS 1 1 (lambda (n) (= 1 (A060990 (A049820 n))))))
CROSSREFS
Cf. A262509 (a subsequence).
Sequence in context: A115839 A200259 A339746 * A130206 A178502 A047322
KEYWORD
nonn
AUTHOR
Antti Karttunen, Sep 25 2015
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 3 18:17 EDT 2024. Contains 373069 sequences. (Running on oeis4.)