OFFSET
0
LINKS
Antti Karttunen, Table of n, a(n) for n = 0..20197
FORMULA
EXAMPLE
a(2) = 1 because there is number m with antisigma(m) = 2; m = 3.
PROG
(PARI)
up_to = 105;
A024816(n) = (n*(n+1)/2-sigma(n));
A231367list(up_to) = { my(v=vector(1+up_to), u); for(n=1, 2+up_to, if((u = A024816(n))<=up_to, v[1+u] = 1)); (v); };
v231367 = A231367list(up_to);
A231367(n) = v231367[1+n]; \\ Antti Karttunen, Jan 19 2025
CROSSREFS
KEYWORD
nonn,changed
AUTHOR
Jaroslav Krizek, Nov 09 2013
EXTENSIONS
Name edited and data section extended to a(105) by Antti Karttunen, Jan 19 2025
STATUS
approved