The OEIS is supported by the many generous donors to the OEIS Foundation.
Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.
Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.
%I #6 Jan 30 2016 16:20:13
%S 22,40,72,104
%N Atomic number of the 2nd transition metal (group 4) in the n-th row of the periodic system of elements.
%C Refers to Titanium=22, Zirconium=40, Hafnium=72, Rutherfordium=104.
%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Periodic_table">Periodic table</a>
%Y Cf. A134984, A138724, A137575.
%K nonn,fini,full,less
%O 4,1
%A _Paul Curtz_, May 02 2008
%E Edited by _R. J. Mathar_, May 21 2009