%I A092384
%S A092384 0,2,2,6,4,1,6,5,8,9,1,4,3,8,5,3,7,7,9,11,2,6,4,10,6,5,8,9,10,13,3,8,5,
%T A092384 12,7,7,9,11,11,15,4,10,6,14,8,9,10,13,12,17,5,3,7,7,9,2,11,6,13,10,6,
5,
%U A092384 8,9,10,4,12,8,14,12,7,7,9,11,11,6,13,10,15,14,8,9,10,13,12,8,14,12,16
%N A092384 Sum of digits of n if n even, else sum of digits of 2n.
%C A092384 Inspired by Luhn algorithm for validating credit cards.
%F A092384 a(n) = sum of digits(if even n then n else 2n)
%e A092384 a(11) = 4 = 2 + 2 (2 and 2 are the digits in 22 = 2 * 11)
%e A092384 a(12) = 3 = 1 + 2 (1 and 2 are the digits in 12)
%t A092384 f[n_] := Plus @@ IntegerDigits[ If[ EvenQ[n], n, 2n]]; Table[ f[n], {n,
0, 90}] (from Robert G. Wilson v Mar 24 2004)
%Y A092384 Cf. A092383, A093150.
%Y A092384 Sequence in context: A129889 A130712 A130728 this_sequence A061915 A138565
A137316
%Y A092384 Adjacent sequences: A092381 A092382 A092383 this_sequence A092385 A092386
A092387
%K A092384 easy,nonn,base
%O A092384 0,2
%A A092384 Semaphore Corporation (help(AT)semaphorecorp.com), Mar 20 2004
%E A092384 Corrected and extended by Ray Chandler (rayjchandler(AT)sbcglobal.net),
Mar 21 2004
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