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(0, 1, 2, 3, 2^2, 5, 2*3, 7, 2^3, 3^2, 2*5, 11, 2^2*3, 13, ...) becomes (0^1 + 2, 3^2 + 2, 5^2 + 3, 7^2 + 3, 3^2 + 2, 5^11 + 2, 2^3 + 13, ...).
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%I #8 Oct 05 2015 03:00:36

%S 2,11,28,52,11,48828127,21,131,29,292,524290,35,60,532,245,8195,11,

%T 3219905755813179726837609,274,35,138,78127,10,1388,1594325,284,15,

%U 1851,1333,48,2213,2189,34,129140165,8245,11,48828127,2190,390,3483,304

%N (0, 1, 2, 3, 2^2, 5, 2*3, 7, 2^3, 3^2, 2*5, 11, 2^2*3, 13, ...) becomes (0^1 + 2, 3^2 + 2, 5^2 + 3, 7^2 + 3, 3^2 + 2, 5^11 + 2, 2^3 + 13, ...).

%e 0^1 + 2 = 0 + 2 = 2 = a(1).

%e 3^2 + 2 = 9 + 2 = 11 = a(2).

%e 5^2 + 3 = 25 + 3 = 28 = a(3).

%e 7^2 + 3 = 49 + 3 = 52 = a(4).

%e 3^2 + 2 = 9 + 2 = 11 = a(5).

%e 5^11 + 2 = 48828125 + 2 = 48828127 = a(6).

%e 2^3 + 13 = 8 + 13 = 21 = a(7).

%e 2^7 + 3 = 128 + 3 = 131 = a(8), etc.

%p pflat2 := proc(nmax) local a, ifs, n, p, c ; a := [0,1] ; for n from 2 to nmax do ifs := ifactors(n)[2] ; for p in ifs do a := [op(a),op(1,p)] ; if op(2,p) > 1 then a := [op(a),op(2,p)] ; fi; od: od: a ; end: pL := pflat2(120) : for n from 1 to nops(pL)-4 by 3 do printf("%d,", op(n, pL)^op(n+1, pL)+op(n+2,pL) ) ; od: # _R. J. Mathar_, Nov 06 2008

%Y Cf. A141269, A141270.

%K nonn

%O 1,1

%A _Juri-Stepan Gerasimov_, Nov 01 2008

%E a(11) corrected, extended by _R. J. Mathar_, Nov 06 2008