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%I #10 Feb 07 2024 09:01:11
%S 1,6,20,40,106,326,568,1294,2071,2323,2603,2867,4467
%N a(1) = 1; for n > 1, a(n) is the smallest positive number such that a(n) - a(n-1) = sopfr(a(n)) + sopfr(a(n-1)), where sopfr(k) is the sum of the primes dividing k, with repetition.
%C The sequence has only 12 terms beyond a(1) = 1 as there is no number k such that k - 4467 = sopfr(k) + sopfr(4467). See A369349 for the number of terms beyond each starting value n.
%p a(3) = 20 as a(2) = 6 and sopfr(20) + sopfr(6) = 9 + 5 = 14, which equals 20 - 6.
%p a(13) = 4467 as a(12) = 2867 and sopfr(4467) + sopfr(2867) = 1492 + 108 = 1600, which equals 4467 - 2867.
%Y Cf. A001414, A369349, A369350, A369351, A369352, A369353.
%K nonn,fini,full
%O 1,2
%A _Scott R. Shannon_, Jan 21 2024
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