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A354089
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Sum of divisors function applied to Pythagorean prime shift: a(n) = sigma(A348746(n)).
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4
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1, 4, 6, 13, 14, 24, 8, 40, 31, 56, 12, 78, 18, 32, 84, 121, 30, 124, 20, 182, 48, 48, 24, 240, 183, 72, 156, 104, 38, 336, 32, 364, 72, 120, 112, 403, 42, 80, 108, 560, 54, 192, 44, 156, 434, 96, 48, 726, 57, 732, 180, 234, 62, 624, 168, 320, 120, 152, 60, 1092, 74, 128, 248, 1093, 252, 288, 68, 390, 144, 448, 72
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OFFSET
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1,2
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LINKS
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FORMULA
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Multiplicative with a(p^e) = (q^(e+1)-1)/(q-1) where q = A348744(A000720(p)).
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PROG
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(PARI)
A348746(n) = { my(f=factor(n)); for(k=1, #f~, if(2==f[k, 1], f[k, 1]=3, if(3==f[k, 1], f[k, 1]=5, if(1==(f[k, 1]%4), for(i=1+primepi(f[k, 1]), oo, if(1==(prime(i)%4), f[k, 1]=prime(i); break)))))); factorback(f); };
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CROSSREFS
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Inverse Möbius transform of A348746.
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KEYWORD
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nonn,mult
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AUTHOR
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STATUS
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approved
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