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A246853
Numbers n such that sigma(n+3) - sigma(n) = n + 3.
4
7, 6285, 4693485, 54028959, 75898473, 724416741, 2359059709, 4901493769, 321212249593, 511578306649, 534245763769, 6158645822473
OFFSET
1,1
COMMENTS
Also numbers n such that A001065(n+3) = A000203(n). - Michel Marcus, Sep 06 2014
a(13) > 10^13. - Giovanni Resta, Jul 13 2015
EXAMPLE
Number 7 is in sequence because sigma(7+3) - sigma(7) = 18 - 8 = 10 = 7 + 3.
PROG
(Magma) [n:n in[1..10^7] | SumOfDivisors(n+3)-SumOfDivisors(n) eq n+3]
(PARI)
for(n=1, 10^7, if(sigma(n+3)-sigma(n)==n+3, print1(n, ", "))) \\ Derek Orr, Sep 05 2014
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Jaroslav Krizek, Sep 05 2014
EXTENSIONS
a(4)-a(8) from Hiroaki Yamanouchi, Sep 10 2014
a(9)-a(12) from Giovanni Resta, Jul 13 2015
STATUS
approved