23103

Appears in sequences

• Discriminants of quintic fields with 2 complex conjugates (negated).at n=43A023684
• Numbers k such that (k+1)*phi(k) is a perfect square.at n=21A069952
• Starting positions of strings of three 5's in the decimal expansion of Pi.at n=22A083620
• Numbers n such that (n+j) mod (2+j) = 1 for j from 0 to 5 and (n+6) mod 8 <> 1.at n=27A096024
• Times in hours, minutes and seconds (to the nearest second) at which the hour and minute hands of an analog clock, if interchanged, continue to indicate some other albeit accurate times, over a complete 12-hour sweep for the slower hand. Leading zeros omitted.at n=30A121577
• a(n) = (2*n+1)*(n+1)*(2*n^2+3*n-1).at n=8A123197
• a(n) = 16n^2 + 32n + 15.at n=37A141759
• a(n) = 64*n^2 - 1.at n=18A158684
• Record numbers of A171063 nonzero period n solutions of x(i)=(x(i-1)+x(i-2)) mod m, as encountered in (n=1,m=1; n=1,m=2; n=2,m=1) antidiagonal order.at n=20A171061
• Record numbers of A171063 nonzero period n solutions of x(i)=(x(i-1)+x(i-2)) mod m, as encountered in (n=1,m=1; n=2,m=1; n=1,m=2) antidiagonal order.at n=21A171062
• Numbers m such that phi(m) = k*phi(m-k) for some number 1 <= k < m - 2.at n=44A266267
• Partial sums of A299255.at n=23A299261
• Numbers of the form 16n^2 + 32n + 15 for which the central region of its symmetric representation of sigma consists of two subparts of sizes 4n+7 and 4n+1, n>=0.at n=31A335574
• a(n) is the first number that is the start of a string of exactly n consecutive numbers in A358350.at n=17A359248
• Long leg of the only primitive Pythagorean triple whose inradius is the n-th odd prime and whose short leg is an even number.at n=34A367335
• G.f. satisfies A(x) = ( 1 + x * (1 + x*A(x)^3) )^2.at n=8A371608