A343191 Squiggle Dot Numbers: numbers generated in a similar way to those in A010790 except that every prime number is divided instead of multiplied. The result is then rounded to the closest integer.
1, 1, 0, 0, 0, 0, 0, 0, 8, 677, 616, 671, 620, 668, 140180, 33643245, 31664230, 33526832, 31762262, 33433960, 14042263246, 6487525619781, 6205459288487, 6475261866247, 3885157119748074, 2525352127836247843, 1772797193741045985945, 1340234678468230765374557, 1294019689555533152775435
Offset: 1
Examples
/ 1*4*6*8*9*10*9*8*6*4*1 \
a(10) = round | ---------------------- | = 677;
\ 2*3*5*7 * 7*5*3*2 /
/ 1*4*6*8*9*10*10*9*8*6*4*1 \
a(11) = round | ------------------------- | = 616;
\ 2*3*5*7*11*7*5*3*2 /
/ 1*4*6*8*9*10*12*10*9*8*6*4*1 \
a(12) = round | ----------------------------- | = 671;
\ 2*3*5*7*11*11*7*5*3*2 /
/ 1*4*6*8*9*10*12*12*10*9*8*6*4*1 \
a(13) = round | ------------------------------- | = 620.
\ 2*3*5*7*11*13*11*7*5*3*2 /
Crossrefs
Cf. A010790.
Programs
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PARI
sqdot(n)={my(s=if(isprime(n),1/n,n));for(k=2,n-1,my(kk=k*k);if(isprime(k),s/=kk,s*=kk));round(s)}; for(k=1,29,print1(sqdot(k),", ")) \\ Hugo Pfoertner, Apr 07 2021