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1,1

Conjecture: sequence is infinite.

Charles R Greathouse IV, Table of n, a(n) for n = 1..1280

a(3)=31 because it is prime and 30=2*3*5, 32=2^5 and 2+3+5 = 2+2+2+2+2 = 10.

Cf. A001414, A190680.

Sequence in context: A189324 A127703 A165667 * A039514 A098797 A271999

Adjacent sequences: A086708 A086709 A086710 * A086712 A086713 A086714

nonn

Jason Earls (zevi_35711(AT)yahoo.com), Jul 28 2003

approved