A093097 Start with a(1) = 3, a(2) = 7; then apply the rule of A093094.

3, 7, 2, 1, 1, 4, 2, 1, 4, 8, 2, 4, 3, 2, 1, 6, 8, 1, 2, 6, 2, 6, 4, 8, 8, 2, 1, 2, 1, 2, 1, 2, 2, 4, 3, 2, 6, 4, 1, 6, 2, 2, 2, 2, 2, 2, 4, 8, 1, 2, 6, 1, 2, 2, 4, 4, 6, 1, 2, 4, 4, 4, 4, 4, 8, 3, 2, 8, 2, 1, 2, 6, 2, 4, 8, 1, 6, 2, 4, 6, 2, 8, 1, 6, 1, 6, 1, 6, 1, 6, 3, 2, 2, 4, 6, 1, 6, 1, 6, 2, 2, 1, 2, 1, 2

Offset

1,1

Links

Paolo Xausa, Table of n, a(n) for n = 1..10000

Example

a(3)=first digit of (a(1)*a(2)), a(4)=2nd digit of (a(1)*a(2)), a(5)=first digit of (a(2)*a(3)), a(6)=2nd digit of (a(2)*a(3))

Mathematica

Fold[Join[#, IntegerDigits[Times @@ #[[#2;; #2+1]]]] &, {3, 7}, Range[100]] (* Paolo Xausa, Aug 18 2025 *)

Prog

(Python)
from itertools import islice
from collections import deque
def agen(): # generator of terms
    a = deque([3, 7])
    while True:
        a.extend(list(map(int, str(a[0]*a[1]))))
        yield a.popleft()
print(list(islice(agen(), 105))) # Michael S. Branicky, Aug 18 2025

Crossrefs

Cf. A045777, A060310, A093094, A093095, A093096, A096381.

Sequence in context: A318215 A086313 A016451 * A343201 A086465 A378077

Adjacent sequences: A093094 A093095 A093096 * A093098 A093099 A093100

Keyword

nonn,base

Author

Bodo Zinser, Mar 20 2004

Status

approved