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The idea of A080497 to A080500 when applied to Euler's phi function i.e. on phi-torial function defined in A001783 yields A001783 itself for obvious reasons. Is there any other such example?
Table of n, a(n) for n=1..38.
a(6) = (6-1)(6-4)= 10.
Cf. A080497, A080498, A072513.
Sequence in context: A056701 A055506 A098088 * A007661 A049891 A135432
Adjacent sequences: A080497 A080498 A080499 * A080501 A080502 A080503
Amarnath Murthy, Mar 19 2003
More terms from Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Apr 06 2003