A255417 Row 7 of Ludic array A255127.

17, 101, 187, 281, 367, 461, 547, 629, 721, 809, 901, 989, 1079, 1169, 1253, 1343, 1433, 1523, 1613, 1697, 1783, 1873, 1963, 2051, 2143, 2231, 2311, 2407, 2491, 2587, 2671, 2759, 2851, 2935, 3029, 3115, 3205, 3295, 3383, 3467, 3557, 3647, 3737, 3823, 3913, 4001, 4091, 4177, 4271, 4357, 4447, 4537, 4619, 4711, 4799, 4885, 4979, 5065, 5155, 5243

Offset: 1

Author

Antti Karttunen, Feb 22 2015

Keywords

• nonn

Links

• Antti Karttunen, Table of n, a(n) for n = 1..10001

Crossrefs

Row 7 of A255127. See A255416 for row 6 and A255418 for row 8.

Programs

PARI

my(L=vector(170170,x,3*x+2^(x%2)), m(n, k)=2^(n\/k*k)\(2^k-1)); for(i=3, 6, L=vecextract(L, 2^#L-m(#L, L[1])-1)); L255417=vecextract(L, m(#L, L[1]));
A255417(n)=n--\5760*510510+L255417[n%5760+1] \\ M. F. Hasler, Nov 17 2024

Python

def A255417(n, S=510510, P=5760):
    try: n -= 1; return A255417.L[n]
    except IndexError: return A255417.L[n%P] + n//P*S
    except AttributeError: L = [x+5-x%2 for x in range(0, S, 3)]
    for k in L[:4]: L = [x for i,x in enumerate(L) if i%k]
    A255417.L = L[::17]; return A255417(n+1) # M. F. Hasler, Nov 17 2024

Scheme

(define (A255417 n) (A255127bi 7 n)) ;; Code for A255127bi given in A255127.

Formula

a(n) = a(n-5760) + 510510 = a((n-1)%5760 + 1) + 510510*floor((n-1)/5760). - M. F. Hasler, Nov 10 2024 and Nov 17 2024